karllark/extinction_ensemble_props: M33 UV Extinction paper release

What's Changed adding docs by @karllark in https://github.com/karllark/extinction_ensemble_props/pull/11 updating M33 data and better plots by @karllark in https://github.com/karllark/extinction_ensemble_props/pull/12 updating M33 data by @karllark in https://github.com/karllark/extinction_ensemble_props/pull/13 Add metallicity by @karllark in https://github.com/karllark/extinction_ensemble_props/pull/15 adding docs for M33 by @karllark in https://github.com/karllark/extinction_ensemble_props/pull/14 Full Changelog: https://github.com/karllark/extinction_ensemble_props/compare/v1.1...v1.2