If built in linux x64, sfarkxtc can't correctly extract files

[moltenform]

I think the issue stems from the code assuming that sizeof unsigned long is 4, but when building in a linux x64 environment, sizeof unsigned long is 8.

Currently, in linux x64, everything appears to build, but decoding any file, even valid files, gives the error Invalid length... Result: Invalid compressed data (file is corrupt) errorcode 7. The issue is also mentioned here: http://linux-audio.4202.n7.nabble.com/sfArk-for-Linux-git-repo-access-td93130.html#a93161

Possible approaches,

• add a static assert+explanation so that it won't build if sizeof unsigned long != 4
• alter the makefiles to make x86 builds. the following worked for me:
  • added a -m32 to the CXXFLAGS and LD sections of the makefiles
  • I needed to install the g++-multilibs and zlib1g-dev:i386 packages
• fix the issue by using a known-length type like uint32_t. Possibly use the patch in the link above.

Which do we think is best? I know I can code at least the first 2.

[moltenform]

This is almost certainly the cause of #13