Automate documentation validation

[eak24]

When documentation is being created (which should be done during the release build step) it is critical to validate that all the publicly exposed functions (which can be assumed to be everything that has a docstring) is fully described. At the very least, check that all the params are present in the function signature. Start by looking here: http://www.sphinx-doc.org/en/master/usage/extensions/coverage.html and see if there are any validating documentation available