title: UITableView add new rows to bottom with animation without reloading entire table
body: <p>I have a UITableView and I want to be able to add new rows to the bottom with animation, I was using <code>tableView reloadData</code> and that was working alright, but I want animation. So I switched over too <code>tableView reloadSections</code> but the problem is if I have say 7 rows visible it animates all 7 of those rows. I only want it to animate adding the new row, and not every row on the screen as if it was being added.</p>
  
  <p>Any idea of how to do this?</p>