Vega Strike Code

Small profile-guided optimization: Unit::nummesh() doesn't really need
to be virtual, and having it so is burning lots of cycles in hot
draw/physics loops, so until it becomes necessary, make it nonvirtual
and inline

Small profile-guided optimization: avoid handling the heap if the new
occluder is going to be excluded anyway (ie: less relevant than the
least relevant occluder in a full heap)

Small profile-guided optimizations:
- replace repeated division with multiplication by reciprocal
- make matrix fillup sequential in memory order

Fix optimized FX update loop to not be infinite

Small profile-guided optimization: update effects backwards to minimize
redundant data movement when removing lights

Small profile-guided optimization: avoid unnecessary work in the physics loop

Small optimization: avoid calling isPlayerStarship when not necessary

Fix typing issue in basemaker initialization

Remove yet another declaration of copysign

Fix build with GCC 6, which already defines copysign in math.h
Windows builds unchecked