TRQ-1624. Add some additional protection against pbs_server deleting valid, running jobs. This was happening due to a false positive - pbs_server thought the mom said that the job no longer existed, when in reality the mom was sending its own update to pbs_server and so it didn't process the incoming connection from pbs_server.
Merge branch '4.1-dev' of https://github.com/adaptivecomputing/torque into 4.1-dev