neutron-vpnaas-dashboard is now not a TC-governed project,
so we don't have an entry in openstack/releases, but deliverable files
in openstack/releases are useful for tracking releases and
we can leverage release tools like 'new-release' from the releases repo.
This commit adds deliverable files to the repo.
Change-Id: I3caeecff393d491637231738f06533082c816dd0