This PR removes the notion of a run id and replaces it with a deploy id in continuous tests. Deploy ids can be set at deploy time only (duh), and will be picked up by the test runner from the deploy file on subsequent runs of the continuous test runner. As a consequence, the deploy id becomes a deployer parameter, and can no longer be overridden at the runner. For non-continuous tests, the deploy ID is created on-the-fly.
