message: Fix Panic w/ Heredocs
  Closes
diff: @@ -350,11 +350,11 @@ impl<'a> Collector<'a> {
  }
  unsafe { String::from_utf8_unchecked(buffer) }
  };
  - let heredoc = heredoc.lines().collect::<Vec<&str>>();
  - // Then collect the heredoc from standard input.
  - inputs.as_mut().map(|x| {
  - x.push(Input::HereString(heredoc[1..heredoc.len() - 1].join("\n")))
  - });
  + let heredoc = heredoc.lines().skip(1).collect::<Vec<&str>>();
  + if heredoc.len() > 1 {
  + let herestring = Input::HereString(heredoc[..heredoc.len()-1].join("\n"));
  + inputs.as_mut().map(|x| x.push(herestring.clone()));
  + }
  }
  } else if let Some(file) = self.arg(&mut bytes)? {
  // Otherwise interpret it as stdin redirection
  