title: How to animate multiple SKSpriteNode together?
body: <p>I am pretty new to <code>SpriteKit</code>. I have a set of nodes that need to move together to a different point for each node and after that animation completed for all of them I would like to do something else. </p>
  
  <p>I was making this with <code>UIView</code> components before. A <code>[UIView animateWithDuration:completion:]</code> block was providing the thing that I needed. But in <code>SpriteKit</code>  each node has its own action and animate by itself. I could not find any block animation for sprite nodes. So I cannot control the animation completion.</p>
  
  <p>Hope, I am clear. Thanks in advance.</p>