ValueError for attempting to infill CFCs before 1765

[chrisroadmap]

Pull request

Please confirm that this pull request has done the following:

• [x] Tests added
• [ ] Documentation added (where applicable) [N/A]
• [ ] Example added (either to an existing notebook or as a new notebook, where applicable) [N/A]
• [x] Description in CHANGELOG.rst added

Adding to CHANGELOG.rst

Please add a single line in the changelog notes similar to one of the following:

- (`#XX <http://link-to-pr.com>`_) Added feature which does something
- (`#XX <http://link-to-pr.com>`_) Fixed bug identified in (`#XX <http://link-to-issue.com>`_)

[codecov[bot]]

Codecov Report

Merging #68 into master will increase coverage by <.01%. The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #68      +/-   ##
==========================================
+ Coverage   97.04%   97.04%   +<.01%     
==========================================
  Files          36       36              
  Lines        1353     1355       +2     
==========================================
+ Hits         1313     1315       +2     
  Misses         40       40

Impacted Files	Coverage Δ
fair/tools/magicc.py	100% <100%> (ø)	:arrow_up:

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