Allow the user to specify custom configuration for the RH-SSO 7.2 for OpenShift and RH-SSO 7.3 CD Technology Preview for OpenShift images via supplied definition of OpenShift ConfigMap.

This could simplify image customization (the need to customize RH-SSO configuration file would be question of editing the ConfigMap, not question of providing custom standalone-openshift.xml in source repository, and rebuilding the image).

Acceptance Criteria:
The RH-SSO server deployed on top of RH-SSO 7.2 / 7.3 TP CD for OpenShift images would still have default standalone-openshift.xml configuration file to be used, if the ConfigMap definition wasn't supplied.

If the RH-SSO ConfigMap definition was supplied, the configuration file from the ConfigMap would be used instead to launch the pod(s).