Actions docs

[jennyfolkesson]

I decided to go with the following for creating a github actions workflow for autopublishing docs:
https://github.com/peaceiris/actions-gh-pages

In my last push I updated the action to only trigger when there's a push to main (which I haven't been able to test), but I've been testing it with this branch and it seems to be working, so hopefully this will work.

I've also added some notes in the docs/readme.md on how to build the html locally and with the workflow.

I've set up a branch named gh-pages where changes in documentation will be pushed to and automatically published from.

Latest version can be seen here:
https://mehta-lab.github.io/microDL

Thank you for giving me permissions to change the Pages settings in order to set this up. I appreciate your help and feedback.

[codecov-commenter]

Codecov Report

Merging #194 (d01e227) into main (91da099) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #194   +/-   ##
=======================================
  Coverage   76.75%   76.75%           
=======================================
  Files          53       53           
  Lines        5090     5090           
=======================================
  Hits         3907     3907           
  Misses       1183     1183           

Flag	Coverage Δ
build	76.75% <ø> (ø)

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[jennyfolkesson]

This PR is ready for another review. I've tested it using the actions_docs.yml workflow seen here:
698c03a
and I'm assuming the behavior will be the same now that I've switched the branch that triggers the action to main. Thanks.