A chess compression library

This crate is a straight port of the Lichess move compression code from Java to Rust, but with a slightly different API. The Rust code passes the same test corpus as the Java code, so it should be compatible with compressed data from that library, but this hasn't been explored beyond passing the test corpus.

lib.rs:

A library for compressing chess moves and positions. The code is straight ports of Java and Scala originals made by the Lichess project, with some tweaks to the API. The code is split into two modules, one for compressing moves and one for positions.