message: add function to require the prompt from user
diff: @@ -62,6 +62,19 @@ impl Term {
  Progress::new_tick(self, 0)
  }
  + pub fn prompt(&mut self, prompt: &str) -> io::Result<String> {
  + use ::std::io::BufRead;
  +
  + let mut out = self.stdout.lock();
  + write!(&mut out, "{}", prompt)?;
  + out.flush()?;
  + let stdin = io::stdin();
  + let mut lock = stdin.lock();
  + let mut output = String::new();
  + lock.read_line(&mut output)?;
  + Ok(output)
  + }
  +
  pub fn password(&mut self, prompt: &str) -> io::Result<String> {
  let mut out = self.stdout.lock();
  write!(&mut out, "{}", prompt)?;
  