Plugin hangs forever if peer on other side dies #7
Description
If there is a conversation going (e.g. an ontology clone or a push), and the peer on the other side is killed/rebooted, Protege will wait for the activity to complete forever and the GUI is frozen because all the menus implement those operations synchronously. This is of course problematic. There are some long running tasks, so the plugin shouldn't block. And also, the presence detection mechanism should result in an error eventually, regardless of whether a particular task is blocking or not! If the remote peer drops from the network, the activity should error out and that error should be shown to the user.