title: Angular-ui's tooltip does not display correctly in ng-grid
body: <p>I've been searching for some time for a solution for displaying a tooltip on ng-grid but with no luck. When I use the cellTemplate on ng-grid for customizing the cell to include a tooltip I have experienced various problems - the tooltip is either not showing up or behaving strangely as shown in a plunker: <a href="http://plnkr.co/edit/MFhwgOvSUFKcyJPse5wf">http://plnkr.co/edit/MFhwgOvSUFKcyJPse5wf</a>. </p>
  
  <p>Have I missed something? Does anyone have a solution for displaying tooltips nicely in ng-grid?</p>
  
  <p>Best regards.</p>