Add sphinx-autodoc-typehits sphinx extension

Since we have some python3 typehints in the code now, there is no need
to duplicate that information in sphinx docstrings.
sphinx-autodoc-typehints reads type annotations and updates :type:
information for :param: and :rtype: for :returns:. The results are the
same as if :param: had been given a type or a :type: directive, so this
is essentially just in service of using the same information for both
type hints/static analysis and for documentation.

There is a bug in the released version in that it does not consider
someone setting a default domain explicitly such as we do in zuul. A
pull request has been submitted that fixes the issue

Change-Id: I900a58eb6503cfee3cdff83e6cc376b5e2da3d44
Depends-On: https://github.com/agronholm/sphinx-autodoc-typehints/pull/19
2 files changed