title: Argument labels '(contentsOfURL:, options:, error:)' do not match any available overloads
body: <p>Followed the spotify swift tuturiol on youtube but currently getting the following error <code>Argument labels '(contentsOfURL:, options:, error:)' do not match any available overloads</code>  for the following line:</p>
  
  <pre><code>if let imageData = NSData(contentsOfURL: imgURL, options: nil, error: &amp;error) {
  </code></pre>
  
  <p>Context</p>
  
  <pre><code>func updateCoverArt() {
      if player?.currentTrackMetadata == nil {
          artworkImageView.image = UIImage()
          return
      }
  
      let uri = player?.currentTrackMetadata[SPTAudioStreamingMetadataTrackURI] as! String
  
      SPTAlbum.albumWithURI(NSURL(string: uri), session: session) { (error:NSError!, albumObj:AnyObject!) -&gt; Void in
          let album = albumObj as! SPTAlbum
  
          if let imgURL = album.largestCover.imageURL as NSURL! {
              dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), { () -&gt; Void in
                  var error:NSError? = nil
                  var coverImage = UIImage()
  
                  if let imageData = NSData(contentsOfURL: imgURL, options: nil, error: &amp;error) {
                      if error == nil {
                          coverImage = UIImage(data: imageData)!
                      }
                  }
  
                  dispatch_async(dispatch_get_main_queue(), { () -&gt; Void in
                      self.artworkImageView.image = coverImage
                  })
  
              })
          }
      }
  }
  </code></pre>