astro-rs: Attempting to port astropy to Rust

https://github.com/eta077/astro-rs

The FITS module is the only one that works; the others are mostly placeholder for now (the science is a little out of my league at the moment), but I was able to use this library to decode FITS files from the recent JWST releases, so I thought that was a sufficient milestone to release a 0.1.0 - reviews and contributions would be greatly appreciated!