fix (skins) skins w/ a root rotation, translation, scale

Fix a special case where the gltf/glb model has a skinned mesh that needs to be transformed by the root rotation, scale, translation. This is a somewhat experimental fix, I've tested with a number of models, however if you see an issue, please let me know and share the model.

For performance it is better to not have a top level scale, translation, and rotation since this calculation will need to be done during animation for the skinned meshes. Instead do the top level scale, translation and rotation on the C3 object in C3.