Update Gatekeeper to ignore the Namespaces that come with OpenShift

The openshift* namespaces need to be ignored as they are provided by Red Hat.

mentioned in merge request !156 (merged)

assigned to @cmays20

mentioned in commit 800a835c

closed with merge request !156 (merged)

mentioned in merge request big-bang/bigbang!2450 (merged)

mentioned in commit big-bang/bigbang@3ef4c257

removed from epic big-bang/pipeline-templates&3 (closed)