title: Connection notification to resume NSOperationQueue
body: <p>I need to download some images from the Internet and right now I'm using <code>NSOperationQueue</code>.</p>
  
  <p>I want to know if it is possible to receive an Internet connection notification to be able to pause/resume the download.</p>
  
  <p>I don't need to freeze the download, but just being able to put it (the <code>NSOperation</code>) back on the queue and wait for connection to start it again would be awesome.</p>
  
  <p>Any ideas?
  :)</p>