Rust Preserves v1.0.0 released

As part of my other implementation efforts, I made enough improvements to the Rust Preserves implementation to warrant releasing version 1.0.0.

This release supports the Preserves data model and the binary and text codecs. It also includes a Preserves Schema compiler for Rust (for use e.g. in and an implementation of Preserves Path.

There are four crates: