Add Auraxis-rs to README.md

[brakenium]

This PR adds Auraxis-rs, a Rust Census library to the readme. At this point the only documentation is a couple of examples and the auto generated Rust API docs, not sure if it should be added already?

Might look into contributing a readme and automatically generating the docs with a GitHub action and publishing them. The base Rust tooling already has the tools to generate these docs locally however.

Any thoughts?