Improve Github Actions Workflow

[charliecooper45]

This is an extension to issue #24. A number of future improvements were identified as part of that issue:

• Additional badges on the readme
• Auto publish documentation
• Linting (cargo clippy)
• Formatting (cargo fmt)
• Auto release management (Github Action generates a release after publish)
• Changelogs
• Matrix testing strategy (test on Mac/Windows too)

[devmannic]

A note about publishing documentation. Unless explicitly disabled in Cargo.toml the API docs will get created by crates.io and published to docs.rs for each cargo publish (ie. each new tag run by the CI) without any more work needed here. However we may also want to setup Github pages to publish docs for the develop branch using the CI.