Change log clean up

[samaloney]

Wasn't doing a good job of keeping the change logs updated. Here and went back and fixed the older 0.1.2 and 0.1.3 log and updated the release notes on GitHub. Should be easier to keep tidy going forward.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.36%. Comparing base (3c8b7d6) to head (bb92d0d).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
stixpy/calibration/transmission.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #201   +/-   ##
=======================================
  Coverage   81.36%   81.36%           
=======================================
  Files          36       36           
  Lines        2458     2458           
=======================================
  Hits         2000     2000           
  Misses        458      458           

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