lib/metro/game.rb
def start!
      @window = Window.new width, height, fullscreen?
      window.caption = name
      window.scene = Scenes.generate(first_scene)
      window.show
    end
def start!
      @window = Window.new width, height, fullscreen?
      window.caption = name
      window.scene = Scenes.generate(first_scene)
      window.show
    end
Creates a window and starts the game with the game parameters.