Paper Submission Release (JOSS)

With this project nearing submission for peer review, I wanted to release a new version to make it clear what was worked on before and after feedback from the reviewers! New to this version is multi-threading support, easier star catalog input, a new pixel grid fitting mode (PCA), and the skeleton of a planned Chisq mode (this last one would be a good first issue for any new contributors!) We may make a few edits between now and submission, but these will be mostly minor cleanup or documentation. Having gone through the instillation process on a few different computers now, we'd like to address some of the quirks that might be different from machine to machine. Open to feedback if any of our instructions on the README.md are unclear! You may also see edits to the paper.md, paper.bib files that we are submitting to JOSS. Regardless,

Happy ShOpt-ing =] !!