Update docs to reference Python 3 and fix syntactical errors.
Review Request #11284 — Created Nov. 16, 2020 and submitted
We now pull down the Python 3 intersphinx map, so that all Python
references will point to the Python 3 docs.
Doc syntax errors within the codebase have been fixed. These were
largely missing backticks, colons, or not escaping something like a
Built the docs. Verified the references and that there were no build