Major revamp. I've been trying to clean up the code. the bzerror stuff

Major revamp. I've been trying to clean up the code. the bzerror stuff
still needs major attention (i.e. removal).

Removed references to uninitialized variables like progName,
smallMode, noisy, etc. Remove functions and code for handling "small"
decompression mode, since it is all unreachable. Remove
total_{in,out}* counters - they are never used. Remove panic()
function and assert_h and their uses because they are all for "should
never happen" circumstances. Replace internal malloc/free wrappers
with xmalloc and free. Remove conditional in if(foo)free(foo);
situations. Remove bogus
	if (sizeof(int) != 4) {
		return BZ_CONFIG_ERROR;
	}
(...etc...) code and code for handling BZ_CONFIG_ERROR. Someone should
go through and change the applet to use well-defined types when
appropriate - it expects sizeof(short)==2 && sizeof(int)==4. Until
this commit these were explicitly checked for, and the applet would
exit if these types were not the right size. (I think this is wrong
even as an interim solution.)

With gcc 3.1 reduces size of binary on i386-linux by about 700 bytes.

Lightly tested.