Allow the LUA API to set animations to meshes as well as the animation speed. Also update animations only when needed.

Support for animation blending, though for some reason it doesn't work.

Don't enable animation transitions by default for many reaosons

Object property to store individual bone positions. LUA can specify a bone name followed by a bone position. No functionality yet. Bone rotation to be added in the following commit

Same system for bone rotation, plus a few other things I missed