Space Race 
- Fixed so meshes not centered in 0,0,0 work properly when generating CollisionShapeOctrees
- Added ability for CollisionShapeOctree to identify needs and choose appropriate subdivision type, now allowing quad-divisions when height is dramatically less than width for example.
- Added Optimize() CollisionShapeOctree that when used removes any unused cells and disallows addition of new polygons.
- Renamed CollissionShapeOctree to CollisionShapeOctree (spelled with 1 s, since I've been stubborn and used double s's earlier).