Animated models

[expenses]

We want to be able to handle some degree of skinned animations within models. This is easy enough to do, but the hard part is instancing. Because we don't have access to storage buffers, we're limited to uniform buffers which have a max size of 65535 (on most hardware?) bytes. A joint transform is 32 bytes, so that's about 2048 joints we can have. A very basic human model might have around 10 joints (2 x left leg, 2 x right leg, 2 x left arm, 2 x right arm, body, head) so we'd be able to instance 200 of those at a time.

[expenses]

Implemented in superconductor: https://github.com/MeetKai/superconductor/pull/5