Supporting Quantile Compression

[Martin Loncaric]

I've recently been developing Quantile Compression, which I believe is the perfect codec to add into Blosc. I've created a ticket here:

https://github.com/Blosc/c-blosc/issues/331

On numerical sequences, to compare q_compress vs say zstd given the same compression time (q_compress level 6 vs zstd level 4),
* q_compress's compression ratio is about 45% higher

* zstd decompresses about 50% faster (but with some improvements this may be bridged, and the gap may be closer in Blosc's setting)

Please let me know what the next steps would be and if anyone could help me in the process.

Thanks,

-Martin