Blender Git Loki

Cleanup: Renamed a number of internal rigidbody functions to clarify
the procedure:

world_build: create rbRigidBody instances for stuff in Scene
validate_*: ensure a rbRigidBody exists for an Object/particle/etc.
sync_*: define Bullet settings for an Object/particle/etc. based
on Blender Scene data
world_apply: copy back data from Bullet after a step to the Blender
Scene data

Conflicts:
source/blender/blenkernel/intern/rigidbody.c