Automatic merge from submit-queue
Support storageclass storage updates to v1
**What this PR does / why we need it**: enable cluster administrators to update storageclasses stored in etcd from storage.k8s.io/v1beta1 to storage.k8s.io/v1.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**: I had a hard time getting the test to work with how it was handling KUBE_API_VERSIONS and RUNTIME_CONFIG. I would appreciate some extra review attention there. Also, I had to hack in a `cluster-scoped` "namespace" to get the verification portions of the test script to work. I'm definitely open to ideas for how to improve that if needed.
**Release note**:
```release-note
Support updating storageclasses in etcd to storage.k8s.io/v1. You must do this prior to upgrading to 1.8.
```
cc @kubernetes/sig-storage-pr-reviews @kubernetes/sig-api-machinery-pr-reviews @jsafrane @deads2k @saad-ali @enj
d621ebce89