Katello-deploy updates


For those that use katello-deploy for deploying different environments that
has been a number of refactorings of late. Some of the naming has changed.
This will affect any custom boxes based off these as well as re-training
yourself to up the correct version.

Previously 'centos6' and 'centos7' represented nightly RPM deployments.
Those now reference the base box that runs no shell and simply brings up
those boxes (which you could not do previously). The nightlies are now
known as 'centos6-nightly' and 'centos7-nightly'. All others remain the