R_MarkLights is now about 3% instead of about 15%, I've lost 8 fps on my
null GL speed test. However, R_AddDynamicLights has jumped up a bit, so I'm
wording if maybe more surfaces are being lit.
glquake.h to mathlib.h (along with the declaration for frustum) and the
extern inline keyworws protected by an ifndef so that mathlib.c can cause
R_CullBox to be compiled publicly. The definition of frustrum has been moved
from its verious locations into mathlib.c.