title: Spritekit Swift particle SKEmitterNode add remove
body: <p>so this is nice for create a particle, but whats the right way to remove it , after the duration, sparkEmmiter.particleLifetime do not remove it automatically</p>
  
  <pre><code>let sparkEmmiter = SKEmitterNode(fileNamed: "MyParticle.sks")
  sparkEmmiter.position = CGPointMake(self.frame.size.width/2, self.frame.size.height/2 - 200)
  sparkEmmiter.name = "sparkEmmitter"
  sparkEmmiter.zPosition = 1
  sparkEmmiter.targetNode = self
  sparkEmmiter.particleLifetime = 1
  
  self.addChild(sparkEmmiter)
  </code></pre>
  
  <p>this solutions produce simulator crash </p>
  
  <pre><code>  var re = SKAction.waitForDuration(1)
    var remove = SKAction.removeFromParent()
    var seq = SKAction.sequence([re , remove])
    sparkEmmiter.runAction(seq)
  </code></pre>