title: How to make UISlider default thumb to be smaller like the ones in the iOS control center
body: <p>I'm working on an app and I have a custom <code>UISlider</code>.<br>
  However, I'm having some issues on how to make the <strong>default</strong> thumb to appear smaller like the ones in the iOS control center.<br>
  Note that I want the same iOS thumb, not a custom thumb image. So far, I've tried <code>thumbRect(forBounds...)</code> but no luck.<br>
  Any suggestions?</p>