OpenShift configuration management
AFAIK neither OpenShift nor Kubernetes itself allow you to externalize services configuration. You should have a bunch of yml/json files somewhere and control their deployment/configuration using CLI tools.

But there is Rancher which in version 2.0 allow us to import external Kubernetes clusters and manage them as Rancher's own environments. 

Description of how this could be done with Rancher you can find here.

FYI: Rancher 2.0 is slowly moving to Beta so it might take time for you to use it in your activities.