message: Add some padding to the `tour` example
diff: @@ -73,6 +73,7 @@ impl UserInterface for Tour {
  let element: Element<_> = Column::new()
  .max_width(Length::Units(500))
  .spacing(20)
  + .padding(20)
  .push(steps.view(self.debug).map(Message::StepMessage))
  .push(controls)
  .into();
  