message: Send correct character sequence with alt key
  Resolves
diff: @@ -365,7 +365,12 @@ impl<'a, N: Notify + 'a> Processor<'a, N> {
  }
  // Didn't process a binding; print the provided character
  - if let Some(string) = string {
  + if let Some(mut string) = string {
  + // from ST
  + if string.len() == 1 && mods.contains(mods::ALT) {
  + string.insert(0, '\x1b');
  + }
  +
  self.ctx.notifier.notify(string.into_bytes());
  self.ctx.selection.clear();
  }
  