This command checks the configuration for invalid and deprecated
settings, as described in
https://governance.openstack.org/tc/goals/stein/upgrade-checkers.html
There is also a script in tools/find_settings.py that scans all python
files for the potential new settings, which is supposed to make it
easier to update the lists that the checks use.
Change-Id: Ie85cf4be3da1ab446c10883a4580e20ea154b67c
Story: 2003657
Task: 26132
