Update changelog for 0.16

[dstansby]

[Description of PR]

TODO:

• Unit tests and/or doctests in docstrings
• Tests pass locally
• Docstrings and API docs for any new/modified user-facing classes and functions
• Changes documented in docs/release.rst
• Docs build locally
• GitHub Actions CI passes
• Test coverage to 100% (Codecov passes)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.96%. Comparing base (b588f0f) to head (887c9e2).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #720   +/-   ##
=======================================
  Coverage   99.96%   99.96%           
=======================================
  Files          63       63           
  Lines        2738     2738           
=======================================
  Hits         2737     2737           
  Misses          1        1           

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[jakirkham]

In the future, @dstansby, could you please start an issue planning for the release? That would allow us to organize any work that we would like to get in with an issue

[dstansby]

👍 Sorry, happy to if it's helpful, but it would be good to list that as a requirement in the release procedure to make sure all developers are on the same page