Added provisions for using Collision Capsules in the physics engine, as well as provisions for rendering them using gluSphere and gluCylinder calls.
Fixed rotation calculation (OpenGL uses Degrees, PhysX uses Radians).
When this eventually is used in a game engine, the PXRigidActor* values for each colliding body will not actually be stored in some array. Each object instance in the world will have a reference to a mesh that is stored in the renderer, so the objects rendered will not necessarily look like the bounding volumes used to represent them physically.

TODO: Consider provisions necessary for constraints (springs, chain links, wheels, etc)

Issues: Default orientation of capsules does not work.