Auto-compress snapshots and load compressed snapshots

[matthewdarwin]

Looking at WAX, for example a snapshot original_size = 21960.4 MiB compressed_size with zstd = 3954.6 MiB It would be great if nodeos compressed the snapshot when writing to disk to save extra i/o.

Various different people have chosen different compression standards for snapshots which makes it hard to build interoperable tools. Having nodeos work with a compression tech directly would enforce consistency by default. I like zstd. On the other hand zlib is already included in nodeos.

This will help a lot on AWS or other cloud providers where I/O is very restricted.

Originally: eosnetworkfoundation/mandel#73