Elric's changes:

Elric's changes:
JPEG texture loading using libjpeg (entirely optional at runtime - if not present, it won't load it)
gl_extensionfunctionlist_t is now renamed dllfunction_t and part of a shared system for library opening/function retrieval (functions Sys_LoadLibrary, Sys_GetProcAddress, Sys_UnloadLibrary - for this the library handles are considered void *'s)
LordHavoc's changes:
fixed libjpeg support in non-win32 by using jpeglib.h - honors jpeglib.h's idea of boolean - Linux libjpeg is compiled with boolean as int, unlike windows where it is apparently byte - unfortunately this also means you need libjpeg-devel installed to compile it in non-win32, not sure what can be done about this (but most people seem to have that anyway...)
looks for libjpeg.so.62 instead of libjpeg.so

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@2610 d7cf8633-e32d-0410-b094-e92efae38249