Add a 'reference' documentation section

[matthewhughes934]

This is a followup to #30

• Add a 'reference' documentation section

  This file contains documentation generated from the library's pydocs. As an example, rewrite the docs for imaplib2.version into a Sphinx compatible format and link to it using Sphinx's autodoc extension[1].

  [1] https://www.sphinx-doc.org/en/master/usage/extensions/autodoc.html

• Add CI job to build docs

  Since docs will be built from source, this job is to help catch any errors e.g. introduced by someone changing pydocs who didn't try to rebuild the docs locally

[codecov[bot]]

Codecov Report

Merging #31 (3219581) into master (0458030) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #31   +/-   ##
=======================================
  Coverage   12.38%   12.38%           
=======================================
  Files           3        3           
  Lines        1413     1413           
=======================================
  Hits          175      175           
  Misses       1238     1238           

Flag	Coverage Δ
py3.6	12.38% <ø> (ø)
py3.7	12.40% <ø> (ø)
py3.8	12.43% <ø> (ø)
py3.9	12.43% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
imaplib2/imaplib2.py	11.82% <ø> (ø)

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[piyueh]

Thanks! Will look into it this weekend.

[piyueh]

Thanks! Merged.