Goal: Allow the expansion of ServiceNetworks 

Problem:
In OpenShift 3.x, we had a procedure for expanding the ClusterCIDR of an existing cluster without disrupting running workloads. We have also seen a lot of customers requesting us to share process on modifying this post installation. Often they need to re-install. We don't have any tested methodologies on what it would take to modify ServiceNetwork CIDR with least cdisruption.

As an outcome of R&D epic: 

1. We need documentation on the process that customer should follow to
   1. Expand existing ServiceNetworks
   2. Modify ServiceNetworks.