Make repo support 'tox -epep8' as we want this to be the first gating
check.
Don't make any actual code changes, just change setup and add files.
Further work is needed to re-organize the code, but that can be in a
separate patch.
This adds support to the irc bot for leaving a review on gerrit based
on the ES query. If it finds a match it will leave a link to the bug.
If it fails to find a match it will leave a link to the wiki page for
debugging test failures.
The unit tests depend on gerritlib change: https://review.openstack.org/#/c/47396/1