title: How to wait for a duration before a sequence is run?
body: <p>I'm making a game with SpriteKit, and when it starts, I have nodes that spawn and fall from the top of the screen:</p>
  
  <pre><code>let wait = SKAction.waitForDuration(0.2, withRange: 0.19)
  let spawn = SKAction.runBlock {
      self.addTears()
  }
  let sequence = SKAction.sequence([wait, spawn])
  self.runAction(SKAction.repeatActionForever(sequence))
  </code></pre>
  
  <p>Before these nodes spawn, I want to wait for a duration of 1 second, but only when the game starts. I tried to add a waitForDuration before I run the sequence but it didn't work.</p>