title: UITableView CoreData order with sections
body: <p>I'm searching around to find some similar scenario but I cannot find anything that contains all features that I need. Looking around I wrote the implementation of the method moveRowAtIndexPath like the following but I have some issue with modifying the reference to the coredata objects so when I click done nothing is saved on coredata.</p>
  
  <pre><code>override func tableView(tableView: UITableView, moveRowAtIndexPath sourceIndexPath: NSIndexPath, toIndexPath destinationIndexPath: NSIndexPath) {
      userDrivenDataModelChange = true;
  
      if (sourceIndexPath == destinationIndexPath) {
          return
      }
  
      let rooms = fetchedResultsController.sections!
  
      let sourceRoom = rooms[sourceIndexPath.section]
      let destinationRoom = rooms[destinationIndexPath.section]
  
      var sourceLights = sourceRoom.objects as! [Light]
      var destinationLights = destinationRoom.objects as! [Light]
      let light = sourceLights[sourceIndexPath.row]
  
      sourceLights.removeAtIndex(sourceIndexPath.row)
      destinationLights.insert(light, atIndex: destinationIndexPath.row)
  
      (destinationLights as NSArray).enumerateObjectsUsingBlock({ object, index, stop in
          let light = object as! Light
          light.position = index
      })
  
      tableView.reloadData()
  
      Utils.saveContext(getAppDelegate().context)
  
      userDrivenDataModelChange = false;
  }
  </code></pre>