Release notes for 0.14

[dstansby]

Release notes for 0.14. I'd like to get #460 in before this, and then do a release.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.54%. Comparing base (23223dc) to head (dbb53f5).
Report is 1 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (23223dc) and HEAD (dbb53f5). Click for more details.

HEAD has 11 uploads less than BASE

Flag	BASE (23223dc)	HEAD (dbb53f5)
	12	1

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #629      +/-   ##
==========================================
- Coverage   99.81%   94.54%   -5.28%     
==========================================
  Files          62       62              
  Lines        2712     2712              
==========================================
- Hits         2707     2564     -143     
- Misses          5      148     +143     

see 9 files with indirect coverage changes