title: Can't clean Notification Center without aps badge or badge = 0?
body: <p>I push to user a notification payload without badge key or badge = 0, the notification can't be removed from Notification Center. Here is my payload:</p>
  
  <pre><code>{
       "aps" : {"alert" : "bala bala"}
  //or "aps" : {"alert" : "bala bala", "badge" : 0}
  }
  </code></pre>
  
  <p>Then open app from NC, the notification stay in NC, can't be removed. If I set badge value greater then 0 in aps, the notification will be removed after app launch.</p>
  
  <pre><code>{
      "aps" : {"alert" : "bala bala", "badge" : 1}
  }
  </code></pre>
  
  <p>I have <strong>already</strong> set <code>[[UIApplication sharedApplication] setApplicationIconBadgeNumber:0];</code> after app launch.</p>
  
  <p>Why notification can't be removed without badge key or badge = 0 ?</p>
  
  <p>Thanks.</p>