Misc. for 0.2.0 release

[brendan-m-murphy]

These are small tasks that should be done before the release:

• [ ] update setup.cfg to include numpyro as a requirement (same for tfpnightly?)
• [ ] update documentation (readme, docstrings, ini files) with all new options
• [ ] update change log (log normal PR missing, look for others)
• [ ] add model-related options to output file attributes
• [ ] write milestone/release description
• [ ] review old issues/PRs and tag them with the milestone, if appropriate
• [ ] run black over all code; check for flake8 suggestions