Dynamic vertex lighting

Updated the Doom 64 source with new dynamic vertex lighting.

It looks weird at times because vertex lighting looks good when you have vertices to light... not a lot to go around here.

Lights for:
player shoots a gun (pistol through chaingun)
player shoots a rocket
player shoots plasma, bfg, laser

lost soul emits light

imp throws fireball
nightmare imp throws fireball
cacodemon spits fireball
hell knight throws fireball
baron of hell throws fireball
mancubus shoots
spider shoots
cyberdemon shoots (double-check that one)

keycards and skull keys