akka/akka — pull request #1432 by patriknw (2013-05-10 17:34:52+00:00)
Title: Hardening of cluster member leaving path, see #3309

* ClusterSingletonManagerSpec revealed a bug in Gossip merge, which
caused a removed member to come back into the member set after
a gossip merge.
* Removed leader commands for Shutdown and Exit
* Member shutdown itself when it sees itself as Exiting
* Singleton cluster with status Exiting will shutdown itself,
in case the Exiting gossip never arrives
* Exiting member not part convergence check
* Exiting member is removed by leader (on convergence) when the
exiting member is in the unreachable set, i.e. sucessfully shutdown
* Reverted the change made for #3266, i.e. Exiting is
detected as unreachable again.
* Removed entry should have higher prio than Exiting and Down in
Gossip merge