Bug 916559 - Existing broker keys broken after stage upgrade

Broker keys used to store login.  Code in sprint24 changed it to use user UUID.  This broke existing broker keys.  Reverting back to original behavior and will update in the future (for identity support where login is != unique/present)
Merge pull request #1536 from smarterclayton/bug_916559_existing_broker_keys_broken

Bug 916559 - Existing broker keys broken after stage upgrade