title: ManagedObject attributes are nil after second reloadData
body: <p>I have value:</p>
  
  <pre><code>private var journeysArray : [JourneyInformation]!
  </code></pre>
  
  <p>In <code>viewWillAppear</code> I load data from Core Data:</p>
  
  <pre><code>        let moc = DataController().managedObjectContext
          let reqest = NSFetchRequest(entityName: "JourneyInformation")
  do {
          journeysArray = try moc.executeFetchRequest(reqest) as! [JourneyInformation]
          journeysTableView.reloadData()
      } catch {
          fatalError("Core data error \(error)")
      }
  </code></pre>
  
  <p>In first reload data all works well, and I can get all needed information, but after second reload:</p>
  
  <pre><code>    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
  
          tableView.reloadData()
  </code></pre>
  
  <p>Attributes in the <code>JourneyInformation</code> object are nil. <code>journeysArray</code> show that it contain 4 objects as before.
  How get objects and works with them without losses?</p>