--- /dev/null
+### GNU GENERAL PUBLIC LICENSE
+
+Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+### Preamble
+
+The licenses for most software are designed to take away your freedom
+to share and change it. By contrast, the GNU General Public License is
+intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.) You can apply it to
+your programs, too.
+
+When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if
+you distribute copies of the software, or if you modify it.
+
+For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
+rights.
+
+We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on,
+we want its recipients to know that what they have is not the
+original, so that any problems introduced by others will not reflect
+on the original authors' reputations.
+
+Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at
+all.
+
+The precise terms and conditions for copying, distribution and
+modification follow.
+
+### TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+**0.** This License applies to any program or other work which
+contains a notice placed by the copyright holder saying it may be
+distributed under the terms of this General Public License. The
+"Program", below, refers to any such program or work, and a "work
+based on the Program" means either the Program or any derivative work
+under copyright law: that is to say, a work containing the Program or
+a portion of it, either verbatim or with modifications and/or
+translated into another language. (Hereinafter, translation is
+included without limitation in the term "modification".) Each licensee
+is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the Program
+(independent of having been made by running the Program). Whether that
+is true depends on what the Program does.
+
+**1.** You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a
+fee.
+
+**2.** You may modify your copy or copies of the Program or any
+portion of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+
+**a)** You must cause the modified files to carry prominent notices
+stating that you changed the files and the date of any change.
+
+
+**b)** You must cause any work that you distribute or publish, that in
+whole or in part contains or is derived from the Program or any part
+thereof, to be licensed as a whole at no charge to all third parties
+under the terms of this License.
+
+
+**c)** If the modified program normally reads commands interactively
+when run, you must cause it, when started running for such interactive
+use in the most ordinary way, to print or display an announcement
+including an appropriate copyright notice and a notice that there is
+no warranty (or else, saying that you provide a warranty) and that
+users may redistribute the program under these conditions, and telling
+the user how to view a copy of this License. (Exception: if the
+Program itself is interactive but does not normally print such an
+announcement, your work based on the Program is not required to print
+an announcement.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote
+it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+**3.** You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+
+**a)** Accompany it with the complete corresponding machine-readable
+source code, which must be distributed under the terms of Sections 1
+and 2 above on a medium customarily used for software interchange; or,
+
+
+**b)** Accompany it with a written offer, valid for at least three
+years, to give any third party, for a charge no more than your cost of
+physically performing source distribution, a complete machine-readable
+copy of the corresponding source code, to be distributed under the
+terms of Sections 1 and 2 above on a medium customarily used for
+software interchange; or,
+
+
+**c)** Accompany it with the information you received as to the offer
+to distribute corresponding source code. (This alternative is allowed
+only for noncommercial distribution and only if you received the
+program in object code or executable form with such an offer, in
+accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+**4.** You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt otherwise
+to copy, modify, sublicense or distribute the Program is void, and
+will automatically terminate your rights under this License. However,
+parties who have received copies, or rights, from you under this
+License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+**5.** You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+**6.** Each time you redistribute the Program (or any work based on
+the Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+**7.** If, as a consequence of a court judgment or allegation of
+patent infringement or for any other reason (not limited to patent
+issues), conditions are imposed on you (whether by court order,
+agreement or otherwise) that contradict the conditions of this
+License, they do not excuse you from the conditions of this License.
+If you cannot distribute so as to satisfy simultaneously your
+obligations under this License and any other pertinent obligations,
+then as a consequence you may not distribute the Program at all. For
+example, if a patent license would not permit royalty-free
+redistribution of the Program by all those who receive copies directly
+or indirectly through you, then the only way you could satisfy both it
+and this License would be to refrain entirely from distribution of the
+Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+**8.** If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+**9.** The Free Software Foundation may publish revised and/or new
+versions of the General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program
+specifies a version number of this License which applies to it and
+"any later version", you have the option of following the terms and
+conditions either of that version or of any later version published by
+the Free Software Foundation. If the Program does not specify a
+version number of this License, you may choose any version ever
+published by the Free Software Foundation.
+
+**10.** If you wish to incorporate parts of the Program into other
+free programs whose distribution conditions are different, write to
+the author to ask for permission. For software which is copyrighted by
+the Free Software Foundation, write to the Free Software Foundation;
+we sometimes make exceptions for this. Our decision will be guided by
+the two goals of preserving the free status of all derivatives of our
+free software and of promoting the sharing and reuse of software
+generally.
+
+**NO WARRANTY**
+
+**11.** BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
+EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
+OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY
+KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
+PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
+THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+**12.** IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
+WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
+AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
+FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
+CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
+PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
+FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
+
+### END OF TERMS AND CONDITIONS
+
+### How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these
+terms.
+
+To do so, attach the following notices to the program. It is safest to
+attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ one line to give the program's name and an idea of what it does.
+ Copyright (C) yyyy name of author
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+Also add information on how to contact you by electronic and paper
+mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+ Gnomovision version 69, Copyright (C) year name of author
+ Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+ type `show w'. This is free software, and you are welcome
+ to redistribute it under certain conditions; type `show c'
+ for details.
+
+The hypothetical commands \`show w' and \`show c' should show the
+appropriate parts of the General Public License. Of course, the
+commands you use may be called something other than \`show w' and
+\`show c'; they could even be mouse-clicks or menu items--whatever
+suits your program.
+
+You should also get your employer (if you work as a programmer) or
+your school, if any, to sign a "copyright disclaimer" for the program,
+if necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright
+ interest in the program `Gnomovision'
+ (which makes passes at compilers) written
+ by James Hacker.
+
+ signature of Ty Coon, 1 April 1989
+ Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library,
+you may consider it more useful to permit linking proprietary
+applications with the library. If this is what you want to do, use the
+[GNU Lesser General Public
+License](https://www.gnu.org/licenses/lgpl.html) instead of this
+License.