Volume units need to install thin-provisioning-tools

[Niels van Adrichem]

In OpenStack with openstack-origin=xenial:pike I ran into a problem with my cinder-units running only the role "volume" that I could not create new volumes. The cinder-volume.log files showed exactly the same symptoms as in this DevStack bug: https://bugs.launchpad.net/devstack/+bug/1615134

Luckily, also the same solution worked, installing thin-provisioning-tools on the cinder-volume units through `apt-get install thin-provisioning-tools`.
I think this package should be added to the charm in case it has the role volume or more enabled.

[Niels van Adrichem (nvanadrichem)]

See pull-request for a solution to merge: https://github.com/openstack/charm-cinder/pull/1

[Niels van Adrichem (nvanadrichem)]

I see that I should have done that through gerrit, though I do not have a gerrit account, can somebody who has apply the attached patch?

[James Page (james-page)]

Already committed under:

  https://review.openstack.org/#/c/518392/

This fix will be included in the charm release later this month; in the meantime switch to using:

  cs:~openstack-charmers-next/cinder

Thanks for the patch!