title: CloudKit: delete CKSubscription is not working
body: <p>Hello i try to cancel a subscription on CloudKit.
  So far i tried both CKModifySubscriptionsOperation and single removement by publicDB?.deleteSubscriptionWithID. My completionHandler gives me no error and an array of the deleted subscription ID's. So all seems to be ok.</p>
  
  <p>But when i change a record i still get a push notification.
  How to remove the subscriptions?</p>
  
  <p>Here is the changed code:</p>
  
  <pre><code>func cancelCubscription(subscription:Subscriptions){
      self._animationDelegate?.beginAnimation()
      var subs = [String]()
      subs.append(subscription.daySubSignature!)
      subs.append(subscription.hdpSubSignature!)
      subs.append(subscription.noteSubSignature!)
      subs.append(subscription.planerSubSignature!)
      subs.append(subscription.subjectSubSugnature!)
      subs.append(subscription.teacherSubSignature!)
      subs.append(subscription.tldSubSignature!)
  
      // Create a CKModifyRecordsOperation operation
      let subscriptionOperation = CKModifySubscriptionsOperation(subscriptionsToSave: nil, subscriptionIDsToDelete: subs)
  
      subscriptionOperation.modifySubscriptionsCompletionBlock = { (modifiedSubscriptions: [CKSubscription]?, deletedSubscriptionIDs: [String]?, error: NSError?) -&gt; Void in
          guard error==nil else {
              dispatch_async(dispatch_get_main_queue(), { () -&gt; Void in
                  self._animationDelegate?.endAnimation()
                  print(error!.localizedDescription)
  
                  let title:String = "Alert_Cancel_CloudKit_Subscription_Error_Title".localized
                  let message:String = error!.localizedDescription
  
                  self._alertDelegate?.showAlert(title, message: message)
              })
              return
          }
  
          dispatch_async(dispatch_get_main_queue(), { () -&gt; Void in
              self._animationDelegate?.endAnimation()
              print("")
              print("- * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - *")
              print("Unscribe to CloudKit subscription success!")
  
              let title:String = "Alert_Cancel_CloudKit_Subscription_Success_Title".localized
              let message:String = "Alert_Cancel_CloudKit_Subscription_Success_Message".localized
  
              self._alertDelegate?.showAlert(title, message: message)
  
              for sub in deletedSubscriptionIDs!{
                  print("Deleted Subscription: \(sub)")
              }
  
              subscription.tldSubSignature = "null"
              subscription.daySubSignature = "null"
              subscription.hdpSubSignature = "null"
              subscription.noteSubSignature = "null"
              subscription.planerSubSignature = "null"
              subscription.subjectSubSugnature = "null"
              subscription.teacherSubSignature = "null"
              subscription.subscribed = false
              Subscriptions.editSubsripction(subscription, context: self.appDel.managedObjectContext)
          })
      }
  
      // Add the operation to an operation queue to execute it
      self._publicDB!.addOperation(subscriptionOperation)
  }
  </code></pre>
  
  <p>my subscriptions are still active:
  <a href="http://i.stack.imgur.com/KSOsQ.png" rel="nofollow">CloudKit Dashboard</a></p>
  
  <p>my log when subscribing:</p>
  
  <pre><code>- * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - *
  CloudKit subscription success
  teacherSubSignature = DE49AAFB-373C-49E5-8DC8-E81A977E7628
  subjectSubSugnature = 3F06E054-D1B9-441E-AED3-CA947820D90C
  daySubSignature = 8FF9AC02-F177-4381-AA8D-08AFFDB0A578
  hdpSubSignature = 811ABA9A-D31B-4661-B783-B5DF033FC5F4
  tldSubSignature = 1C07C661-02A9-48F3-9B92-08F41433E179
  planerSubSignature = 1C32F1F0-3647-4F57-BDEF-215A28F69039
  hdpSubSignature = 59216B52-1A21-4666-950A-F8CDE44591D2
  Subscription Edited in Core Data
  </code></pre>
  
  <p>and on delete subscription:
      error = nil</p>
  
  <pre><code>- * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - *
  Unscribe to CloudKit subscription success!
  
  Deleted Subscription: 8FF9AC02-F177-4381-AA8D-08AFFDB0A578
  Deleted Subscription: 59216B52-1A21-4666-950A-F8CDE44591D2
  Deleted Subscription: 811ABA9A-D31B-4661-B783-B5DF033FC5F4
  Deleted Subscription: 1C32F1F0-3647-4F57-BDEF-215A28F69039
  Deleted Subscription: 3F06E054-D1B9-441E-AED3-CA947820D90C
  Deleted Subscription: DE49AAFB-373C-49E5-8DC8-E81A977E7628
  Deleted Subscription: 1C07C661-02A9-48F3-9B92-08F41433E179
  Subscription Edited in Core Data
  </code></pre>