Implement support for quantization

[lukstafi]

The part that's a bit confusing is dynamic indexing. For consistency, the underlying integers still need to be scaled before becoming the indexing integers.

[lukstafi]

It's probably more interesting than it is practical...

[lukstafi]

Let's consider this together with figuring out how to support Float16.

[lukstafi]

This isn't really worthwhile, we would rather need the significantly harder support for quantization.