In order to reduce the packages required to pip install on to the hosts,
we allow the service setup to be delegated to a specific host, defaulting
to the deploy host. We also switch as many tasks as possible to using the
built-in Ansible modules which make use of the shade library.
The 'virtualenv' package is now installed appropriately by the openstack_hosts
role, so there's no need to install it any more. The 'httplib2' package is a
legacy Ansible requirement for the get_url/get_uri module which is no longer
needed. The keystone client library is not required any more now that we're
using the upstream modules. As there are no required packages left, the task
to install them is also removed.
With the dependent patches, the openstack_openrc role is now executed once
on the designated host, so it is no longer required as a meta-dependency for
the role.
Depends-On: https://review.openstack.org/579233
Depends-On: https://review.openstack.org/579959
Change-Id: I20186fd3bb4a3fade91e14f6360232454de9c989
9d01669487