Release Checklist for v2.1

Right now, we're entering a string-freeze and feature-freeze period for the v2.1 release (intended for 23 October). Here's an initial checklist - this will update as bugs / issues appear.

If you're experiencing bugs, please post below so we can squash them before the release.

• [ ] Testing and Bug Fixing
  • [ ] Particularly on Windows
  • [x] https://github.com/OpenChemistry/avogadrolibs/issues/3083
  • [ ] Adding additional automated testing for all file formats
    • [ ] https://github.com/OpenChemistry/avogadrolibs/issues/3099
    • [x] https://discuss.avogadro.cc/t/fixing-space-group-perception-for-cif-files/7544
• [ ] Code quality "good first issues"
  • [x] https://github.com/OpenChemistry/avogadrolibs/issues/3103
  • [ ] https://github.com/OpenChemistry/avogadrolibs/issues/3101
  • [ ] https://github.com/OpenChemistry/avogadrolibs/issues/3100
• [ ] Translation / i18n updates
• [ ] Documentation Updates
  • [ ] "What's new in 2.1"
  • [ ] Top Plugins / Plugin Directory
  • [ ] More Task-Based Tutorials for "Missing" Features (e.g., from survey)