Knowing what services and what versions of those services exist on a
cloud isn't always a spectacular experience. Add a command that will use
get_all_version_data from keystoneauth to produce a report of the
available services and the version info for each service.
Depends-On: https://review.openstack.org/584944
Change-Id: I84751c175d0c5f6d857a5473d2db6d5f1b41f946
Monty Taylor