XD-1949b - Ensure DSM matrix is diagonal

* Created new exception, the somewhat odd named
  BatchJobAlreadyExistsInRegistryException, that replaces the
  BatchJobAlreadyExistsException that references absence in the JobLocator.
* This exception block can likely be since this BBP should only be processing
  jobs that were not deployed.  Created https://jira.spring.io/browse/XD-2014
  to track.