message: println -> writeln, use {:#?}
diff: @@ -345,7 +345,7 @@ pub fn cat( mut term: Term
  let blk = rblk.decode().unwrap();
  if debug {
  - println!("{:?}", blk);
  + writeln!(term, "{:#?}", blk).unwrap();
  } else {
  blk.pretty(&mut term, 0).unwrap();
  }
  @@ -458,7 +458,7 @@ pub fn verify_chain( mut term: Term
  let rblk = rblk.unwrap();
  let blk = rblk.decode().unwrap();
  let hash = blk.get_header().compute_hash();
  - println!("block {} {}", hash, blk.get_header().get_blockdate());
  + writeln!(term, "block {} {}", hash, blk.get_header().get_blockdate()).unwrap();
  match cardano::block::verify_block(blockchain.config.protocol_magic, &hash, &blk) {
  Ok(()) => {},
  Err(err) => {
  