Misc fixes to IBO code to correctly use sizeof(glIndex_t)
OpenGL2: Small optimizations and comments in world VBO creation and surface merging.
OpenGL2: Remove srfTriangle_t, and use glIndex_t instead.
Fix VM FOpenFile( FS_READ ) files seeking twice in FS_Seek
Remove unused variable baseOffset from fsh[]
Support FS_SEEK_END and negative offset for zipped files in FS_Seek

Use FS_SEEK_END in sound code instead of working around it.
If FS_SEEK_SET and going to current position, just return.
Remove old comment that FS_Seek doesn't work on zipped files
Remove function prototypes for non-existant Sys_* DLL functions
Merge branch 'glindex_size_fixes' of https://github.com/inolen/ioq3 into inolen-glindex_size_fixes
Fix flares being invisible after vid_restart

flareCoeff was only set if r_flareCoeff cvar was set as modified.
Cvars are set as modified when created or changed.
Merge remote-tracking branch 'ioquake3/master'

Conflicts:
	code/renderergl2/tr_bsp.c