undo: add device related undo commands

Add commands for deleting devices and editing device nicknames
to include the device-handling in the undo system.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

core/subsurface-qt/divelistnotifier.h

@@ -130,6 +130,7 @@ signals:
 	// Devices related signals
 	void deviceAdded(int index);
 	void deviceDeleted(int index);
+	void deviceEdited(int index);
 
 	// Filter related signals
 	void filterPresetAdded(int index);