Test, build and publish packages for the right distro and branch
Test, build and publish packages for the right distro and branch

- Ensure we always run delorean with the right target, source
  and baseurl parameters.
  This happens before every build now: Allowing to re-run the
  script immediately without the assumption that the workspace
  will be cleaned before the next build. Yields a better UX for
  running on a local machine.
- Ensure we don't build packages for Fedora unless it's for
  the master branch
- Little bit of cleanup and use rsync instead of cp, it's
  faster.

For example, if a commit is made to rpm-liberty, it should
pull the package from stable/liberty, have the baseurl
of the liberty repository and only build CentOS packages.

Change-Id: I4bdff33135f6c55357fafc59161fe69fc98f34a4

openstack-packages/DLRN,openstack-packages/delorean,openstack-packages/delorean,openstack-packages/DLRN