Return cumulative dispatch weight of messages from the messageLane_proveMessages (#469)

* implement OutboundLaneApi and InboundLaneApi for Millau /Rialto runtimes

* fixed typo

bridges/bin/millau/node/src/service.rs

@@ -222,6 +222,7 @@ pub fn new_full(config: Configuration) -> Result<TaskManager, ServiceError> {
 				finality_proof_provider.clone(),
 			)));
 			io.extend_with(MessageLaneApi::to_delegate(MessageLaneRpcHandler::new(
+				client.clone(),
 				backend.clone(),
 				Arc::new(MillauMessageLaneKeys),
 			)));