libbb: inntroduce and use bb_pstrcmp() and qsort_string_vector()

libbb: inntroduce and use bb_pstrcmp() and qsort_string_vector()
msh: glob0/glob1/glob2/glob3 are just a sorting routine! remove them.

bb_pstrcmp                                             -      25     +25
qsort_string_vector                                    -      24     +24
expand                                              2209    2227     +18
getopt32                                            1359    1370     +11
passwd_main                                         1072    1074      +2
handle_incoming_and_exit                            2737    2735      -2
UNSPEC_print                                          66      64      -2
forkexec                                            1343    1339      -4
input_tab                                           3338    3330      -8
get_dir                                              185     177      -8
expmeta                                              481     473      -8
cmdputs                                              405     397      -8
xstrcmp                                               12       -     -12
find_pair                                            187     167     -20
match_compare                                         25       -     -25
dir_strcmp                                            25       -     -25
glob2                                                 27       -     -27
glob3                                                 34       -     -34
glob1                                                256       -    -256
------------------------------------------------------------------------------
(add/remove: 2/6 grow/shrink: 3/8 up/down: 80/-439)          Total: -359 bytes