title: Animate adding/removing UISearchBar to/from UITableView tableViewHeader
body: <p>I have a subclass of UITableViewController. I have code that can add/remove a UISearchBar to/from the tableHeaderView of my tableView. Here's the code I have to perform these tasks:</p>
  
  <pre><code>self.tableView.tableHeaderView = uiSearchBar; //Make the search bar appear
  self.tableView.tableHeaderView = nil; //Make the search bar disappear
  </code></pre>
  
  <p>The problem is that I want the adding/removing of the UISearchBar to be animated; slide into view from the top when I add it then slide upwards and out of view when I remove it instead of just appearing and disappearing. Any suggestions?</p>
  
  <p>Thanks.</p>