message: add rpc message
diff: @@ -19,6 +19,14 @@ pub struct GetCounterMessage {}
  #[derive(Debug, Serialize, Deserialize, Eq, PartialEq, Message)]
  pub enum PeerMessage {
  UserTransaction(SignedUserTransaction),
  + //RPC(RPCMessage),
  +}
  +
  +/// message from peer
  +#[rtype(result = "Result<()>")]
  +#[derive(Debug, Serialize, Deserialize, Eq, PartialEq, Message)]
  +pub enum RPCMessage {
  +
  }
  #[derive(Clone, Hash, Debug)]
  