A conformance test is a test you run against a cluster that is already
set up.  We would use it to test a hosted kubernetes service to make
sure that it meets a bar for quality.  Also, a getting-started-guide
author, who has not implemented a complete set of cluster/...
scripts (that is, the getting-started-guide has some non-automated steps)
can use this to see which e2e tests pass on a cluster.

To be done in future PRs:
- disable tests which can't possibly run in a conformance test
  because they require things like cluster ssh.
- document that when we accept a getting-started-guide, that
  people should run the conformance test against their cluster
  (unless they already have cluster/... scripts.

I ran this against a GCE cluster and 22 tests passed.