stop destination's thread before cleanup

libi2pd/Destination.cpp

@@ -180,6 +180,7 @@ namespace client
 			i2p::tunnel::tunnels.StopTunnelPool (m_Pool);
 		}
 		SaveTags ();
+		m_Service.stop (); // make sure we don't process more messages after this point. TODO: implement it better
 		CleanUp (); // GarlicDestination
 	}
 

libi2pd/RouterContext.cpp

@@ -75,6 +75,7 @@ namespace i2p
 			if (m_CongestionUpdateTimer)
 				m_CongestionUpdateTimer->cancel ();
 			m_Service->Stop ();
+			CleanUp (); // GarlicDestination
 		}	
 	}