Snapshot resource disambiguation

[joekelley]

If two resources have the same Kind but different GroupVerisons, there can be ambiguity in the snapshot interfaces. See this example in Service Mesh Hub, where SMH and App Mesh both provide CRDs called "Mesh": https://github.com/solo-io/service-mesh-hub/pull/938/files#r495074978.

Harvey's recommendations for handling this are to update generated snapshots with one or both of:

1. an optional name alias for resources in the snapshot
2. group snapshot resources under a named GVK interface