OF-751: Fix NPE (PubSub) during shutdown
OF-569: DeleteUser ad hoc command

Per patch submitted by John Georgiadis
OF-562: Fix persistence for MUC room broadcast

Ensure "bits" are present by zero-padding the broadcast roles string
OF-774: Remove extraneous getInstance

AuthorizationManager defines only static methods; no need to
instantiate.
OF-2: Logging for common exceptions less verbose

Modified older patch submitted by David Horowitz to accommodate more
recent changes.