![only works with r_UseGpuSkinning 0]!
- Writes bmd5anim for each animation. its not perfect yet but, rot + trans looks good.
- Model tag supports gltf Animations. Indexed the same way as meshes.
- Enabled weights and bone index in ConvertFromMeshGltf
Loading the collision model from binary can fail, but this wasn't
checked, so idCollisionModelManagerLocal::models[i] could contain NULL
which causes crashes later.