Nuclei.Communication: Define an event to indicate that a remote endpoint is signing off

[pvandervelde]

From @pvandervelde on December 3, 2013 20:59

At the moment there is no real way an application is notified that a remote endpoint is about to sign off which means there is no way for the application to disconnect from events etc.. By providing an event for this we allow applications to disconnect from events etc..

Note that disconnection should succeed even if the remote endpoint is already disconnected.

Copied from original issue: thenucleus/Nuclei#5