We have multiple places, such as bridge, where we use openstackclient
as a utility. The current practice tends to be installing it into a
venv somewhere. On bridge there are 16 venvs in /root - and in some
of them but not all exist a working openstack client.
Since it's purely an API interaction tool, all it needs is the
clouds.yaml files bind-mounted in. The openstackclient project
now publishes a container image. Install a wrapper script for
calling it into /usr/local on bridge.
Change-Id: I4c64125d5dd3c89275e259a57b0efa0847ac6fc2