Improved mesh collision object generation, Added the ability to
construct compound collision objects from meshes.
Added the ability to get and set the physics time step.
Added support for static concave meshes, added the ability to set the
max slope for the Physics Character class.
Added collision mask support, converted RayTestResult and
CollisionResult to classes for use with Lua.
Added getAllEntitiesInRay to the CollisionScene class.
Added documentation on how to use SHAPE_MESH_COMPOUND and
SHAPE_MESH_CONCAVE.
Added global resource autoreload settings
Bezier curve based animation now properly samples curves based on x (not t) except for quaternion curve animations, entity mouse events now contain ray depth information, entity editor will now select closest entity at first click, added visibility layers to SceneEntityInstance and visibility layer sheets to the entity editor
Fixed layer editor icons in non-retina mode
Fixed polyimport not taking entity parent transforms into account on import
Merge remote-tracking branch 'origin/PhysicsImprovements'