Add sphinx documentation

[neishm]

Should probably document the Python interface, and add some examples? Some simple examples are in the root README.md, but could have some more detailed examples in separate .rst files? Need to figure out long-term were the examples will reside - already have stuff int the README.md, and on the internal (CMC) wiki, so now adding .rst files as a third location? Is this situation sustainable?

Should also find the best way to maintain French translations for docs (for reference: https://www.sphinx-doc.org/en/master/usage/advanced/intl.html)

Received some instructions from Sebastien Fortier for setting up sphinx docs, need to try it out.

[neishm]

With the help of Sebastien's documentation setup, I managed to get some sphinx documentation generated from a notebook. It's internal for now. Could make a copy on the public side once docs are more complete.