title: Aligning UIToolBar items
body: <p>I have three <code>UIBarButtonItem</code> created as below. They align left and I'd like to align center so there isn't a gap on the right side. I don't see an align property on <code>UIToolBar</code>. Is there another way to accomplish this?</p>
  
  <pre><code>//create some buttons
  UIBarButtonItem *aboutButton = [[UIBarButtonItem alloc] initWithTitle:@"About" style:UIBarButtonItemStyleBordered target:self action:@selector(showAbout:)];
  [toolbar setItems:[NSArray arrayWithObjects:settingsButton,deleteButton,aboutButton,nil]];
  //Add the toolbar as a subview to the navigation controller.
  [self.navigationController.view addSubview:toolbar];
  </code></pre>