add zstd support

[uli42]

see zstd

"In other words, compared with zlib, Zstandard scales:
At the same compression ratio, it compresses substantially faster: ~3-5x.
At the same compression speed, it is substantially smaller: 10-15 percent smaller.
It is almost 2x faster at decompression, regardless of compression ratio; the command line tooling numbers show an even bigger difference: more than 3x faster.
It scales to much higher compression ratios, while sustaining lightning-fast decompression speeds."