lib/metro/scene.rb
def register_animations!
      self.class.animations.each do |animation|
        animate animation.actor, animation.options, &animation.on_complete_block
      end
    end
def register_animations!
      self.class.animations.each do |animation|
        animate animation.actor, animation.options, &animation.on_complete_block
      end
    end
Register all the animations that were defined for this scene.