This ensures we have version-specific references to other projects [1].
Note that this doesn't mean the URLs are actually valid - we need to do
more work (linkcheck?) here, but it's an improvement nonetheless.

[1] https://docs.openstack.org/openstackdocstheme/latest/#external-link-helper

Change-Id: I118e4d211617c5df66ff04dc04e308a1d2fc67ad

Add an enable_cinder_backend_quobyte option to etc/kolla/globals.yml to
enable use the Quobyte Cinder backend.
Change the bind mounts for /var/lib/nova/mnt to include the shared
propogation if Quobyte is enabled.
Update the documentation to include a section on configuring the Cinder.

Implements: blueprint cinder-quobyte-backend

Change-Id: I364939407ad244fe81cea40f880effdbcaa8a20d