This repo is now testing only with Python 3, so let's make
a few cleanups:
- Remove python 2.7 stanza from setup.py
- Remove obsolete sections from setup.cfg
- Use newer openstackdocstheme and Sphinx versions,
enable build warnings and fix problems
- Cleanup */source/conf.py to remove now obsolete content.
- Remove install_command from tox.ini, the default is fine
- Remove usage of pip_install role, this is retired now
Change-Id: I64133e987965d02faa25102b98ad102ff9ef142b
038a7f29b4