v0.9.0

Prior versions were all about proving out the idea, and now that we've proven it works it's time to clean it up and get it across the 1.0 line.
That means going through the entire codebase and ensuring it will be maintainable going forward, well tested, and working like we want.

Full details at https://ruckstack.org/blog/2020/12/ruckstack-0.9.0-released/