Implementing storage regression tests to match gcloud-node.

Not meant to be merged. Some missing features were
uncovered or hard to use APIs and I want to discuss here
and then map out the plan (i.e. how to break this up).
Can we file a follow-up bug and handle after? I am trying to reach parity with `gcloud-node` regression tests. We should also make sure the node folks are aware of us adding support for this.