TODO

Finish implementing animated sprite support.
Add functionality to handle sliced images gracefully.
Handle render target images gracefully (use heuristics to determine if they're normal render targets like the engine uses, or temporary ones used by mods to generate overlays)
Update the memory cache to hook SMAPI/CP's store. This could eliminate a large swath of allocations.
Update the cache system overall to hook SMAPI/CP's store, to potentially eliminate a number of D3D callbacks.