Create mechanism for ResourceFlavors upgrades

[PBundyra]

What would you like to be added:
If a Workload is scheduled on a less desired RF, and sufficient quota becomes available in the more desired ResourceFlavor, I would like to move the Workload to the more desirable ResourceFlavor.

Why is this needed:

Completion requirements:

This enhancement requires the following artifacts:

• Design doc
• API change
• Set of code changes
• Docs update

The artifacts should be linked in subsequent comments.

[PBundyra]

/assign