title: strange error because of casting tableviewCell
body: <p>i double checked the storyboard and i have set the class of the cell correctly and here is the code that generates the warning </p>
  
  <pre><code>func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -&gt; UITableViewCell {
      //self.table.registerClass(UITableViewCell.self, forCellReuseIdentifier: "swiper")
      var cell:SWTableViewCell = tableView.dequeueReusableCellWithIdentifier("swiper", forIndexPath: indexPath) as! SWTableViewCell
      //cell = SWTableViewCell()
      cell.delegate = self
      if (UIDevice.currentDevice().systemVersion.toInt() &gt;= 7) {
          cell.layoutMargins = UIEdgeInsetsZero
      }
      //circ(cell.layer)
  
      cell.leftUtilityButtons = self.leftButtons() as [AnyObject]
      cell.rightUtilityButtons = self.rightButtons() as [AnyObject]
      /*
      //cell.setCellHeight = cell.frame.size.height*/
      println(indexPath.section)
      return cell
  }
  </code></pre>
  
  <p>and the warning disappear if i comment the dequeue line and uncomment this: cell = SWTableViewCell()
  and the warning generates each time to dequeue a cell and the warning is : </p>
  
  <pre><code>Unable to simultaneously satisfy constraints.
      Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
  (
      "&lt;NSAutoresizingMaskLayoutConstraint:0x7cc50870 h=--&amp; v=--&amp; H:[UITableViewCellContentView:0x7cc50bc0(0)]&gt;",
      "&lt;NSLayoutConstraint:0x7cc477c0 SWUtilityButtonView:0x7cc53bb0.width &lt;= UITableViewCellContentView:0x7cc50bc0.width - 90&gt;"
  )
  
  Will attempt to recover by breaking constraint 
  &lt;NSLayoutConstraint:0x7cc477c0 SWUtilityButtonView:0x7cc53bb0.width &lt;= UITableViewCellContentView:0x7cc50bc0.width - 90&gt;
  
  Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
  The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in &lt;UIKit/UIView.h&gt; may also be helpful.
  2015-08-26 15:08:06.259 swipeTableView[2978:78305] Unable to simultaneously satisfy constraints.
      Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
  (
      "&lt;NSAutoresizingMaskLayoutConstraint:0x7cc50870 h=--&amp; v=--&amp; H:[UITableViewCellContentView:0x7cc50bc0(0)]&gt;",
      "&lt;NSLayoutConstraint:0x7bf92b90 SWUtilityButtonView:0x7cc536e0.width &lt;= UITableViewCellContentView:0x7cc50bc0.width - 90&gt;"
  )
  
  Will attempt to recover by breaking constraint 
  &lt;NSLayoutConstraint:0x7bf92b90 SWUtilityButtonView:0x7cc536e0.width &lt;= UITableViewCellContentView:0x7cc50bc0.width - 90&gt;
  
  Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
  The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in &lt;UIKit/UIView.h&gt; may also be helpful.
  </code></pre>