message: support for err in block header response (part 2)
diff: @@ -427,6 +427,9 @@ pub mod command {
  println!("{}", l);
  match l {
  + packet::BlockHeaderResponse::Err(_t) => {
  + Err("block header response failed")
  + },
  packet::BlockHeaderResponse::Ok(mut ll) => {
  match ll.pop_front() {
  Some(bh) => Ok(bh),
  