Automatic merge from submit-queue
phase 2 of cassandra example overhaul
Here's the next iteration in overhauling this example, towards https://github.com/kubernetes/kubernetes/issues/20961. This removes the pod adoption part, but doesn't (yet) otherwise change any of the resources used.
It also includes some README cleanup, and removes some explicit specification of labels in the rc yaml.
This PR doesn't yet add any commentary on how we're using the seed provider (re: https://github.com/kubernetes/kubernetes/issues/20961#issuecomment-190405959 etc.). Maybe we should add that.
Also: LMK if this PR should include any changes to the links out to the docs.
cc @bgrant0607 @johndmulhausen
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