message: Add help to substitute macros
diff: @@ -1521,6 +1521,7 @@ fn substitute_macros(input: &str) -> String {
  ("[ERROR]", "error:"),
  ("[WARNING]", "warning:"),
  ("[NOTE]", "note:"),
  + ("[HELP]", "help:"),
  ("[DOCUMENTING]", " Documenting"),
  ("[FRESH]", " Fresh"),
  ("[UPDATING]", " Updating"),
  