title: UITextField attributedPlaceholder has no effect
body: <p>I'm trying to make the placeholders in my textfields italic, and since my app is targeting iOS 6.0 or newer, decided to use <code>attributedPlaceholder</code> property instead of rolling something more custom. The code goes as follows:</p>
  
  <pre><code>NSString *plString = @"optional";
  NSAttributedString *placeholder = [[NSAttributedString alloc] initWithString:plString
          attributes:@{NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-LightItalic" size:15]}];
  for (UITextField *t in myTextfields){
      t.placeholder = plString;
      t.attributedPlaceholder = placeholder;
  }
  </code></pre>
  
  <p>Yet the styling of the placeholder still is not italic, but the same as regular text, just dimmer. What am I missing to make the <code>NSAttributedString</code> work?</p>