Zarr v3 codec support

[asinghvi17]

From zarr-developers/numcodecs#524 it looks like zarr-v3 has a narrower definition of codecs. There isn't much detail at the moment, but I wanted to at least mention it and maybe start the discussion of how we should support such codecs in Zarr.jl.

Do we want to support both zarr-v2 and zarr-v3 in the same codec? Some of the codec names and parameters have changed, so do we want to have getCompressorv2 and getCompressorv3 functions separately?

[asinghvi17]

Also, would we want to factor out to a NumCodecs.jl library of our own at some point?

[mkitti]

@meggart @asinghvi17 and @bjarthur

I have version 3 prototype on this branch:
https://github.com/mkitti/Zarr.jl/tree/mkitti-v3-prototype

This currently combines #180 and #182 with some additional changes.