cleanup, fixes, and optimizations

cleanup, fixes, and optimizations

 - remove secondary color fog mode in GL1
 - remove old/dead code
 - optimize drawing functions a bit
 - let GL do more of the clipping work (for aabitmaps)
 - reorganize GL1 texture fucntions to better match previous GL2 fixes
 - remove unnecessary -1 from SDL_snprintf's in cmdline
 - fix b0rked textures in wxGL
 - faster drawing of mouse cursor in flip()
 - glClear after flip in GL1 (better fullscreen/window fix)
 - fix scaling of movies on viewport resize in GL1
 - remove u/v_scale from GL2 (always 1.0 anyway)
 - set_cull(1) in wxGL during init
 - proper cleanup() for wxGL