README Update needed for OpenShift Demos

[taruch]

There are some nuances with the OpenShift demos that requires some changes to be made to the README.

Include this in the PRE-SETUP section of the README.:
The first JT that needs to be run is the install operator JT. This step was intentionally not included in the OPENSHIFT / CNV / Infra workflow job template, however without running it the other JT's won't run.

Include this in the Suggested Usage section of the README.:

• Consistent outage after deploying CNV VMs that users need to be aware of. Sometimes this requires stopping a VM before it settles.
• Inventory update requires that all VMs are running or it fails - the error msg is a bit of a red herring.
• Inability to deploy more than 2 CNV VMs.