This makes it possible to pull images from Docker Hub through the local
container image registry in the CI OpenShift deployment. The registry in
the CI is configured with the 'cephcsibot' account so that pulling
images is accounted towards the account, and not anonymous consumers
within the whole CentOS CI.
There should be no need to manually sync the images between the local
registry and Docker Hub anymore.
Signed-off-by: Niels de Vos <ndevos@redhat.com>