title: Section Headers in UITableView when inset of tableview is changed
body: <p>I have implemented a "Pull to refresh" in my tableView like the iPhone app Twitter or Facebook.<br>
  My tableView has sections with head views. When the tableView is in "Refresh mode", so when I pulled the tableView to refresh, I set the contentInset of the tableView to display the tableView a certain way. At this moment, if I push the tableView up, the headers of the UITableView are not anymore scrolling to the top of the UITableView. See the following screenshots:  </p>
  
  <p><img src="https://i.stack.imgur.com/jLVTa.png" alt="screenshot 1"></p>
  
  <p><img src="https://i.stack.imgur.com/7m83P.png" alt="screenshot 2"></p>
  
  <p>How can I fix that to make the headers scroll like expected?</p>
  
  <p>Thanks!</p>