Fix bug in event unregistration; be sure to null out the handle so it tries to connect later. We started seeing this with pubsub when the server dies, so I expect our failure mode is different!
Fix bug in event unregistration; be sure to null out the handle so it
tries to connect later. We started seeing this with pubsub when the
server dies, so I expect our failure mode is different!

nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome