message: add hash of the node method
diff: @@ -193,6 +193,14 @@ impl NodeData {
  let mut cursor = std::io::Cursor::new(buf);
  Self::read(consensus_branch_id, &mut cursor)
  }
  +
  + pub fn hash(&self) -> [u8; 32] {
  + let mut buf = [0u8; 32];
  +
  + let bytes = self.to_bytes();
  +
  + blake2b_personal(&personalization(self.consensus_branch_id), &bytes)
  + }
  }
  #[cfg(test)]
  