title: How do I add whitespace using GWT 2.4 and uiBinder?
body: <p>I'm working on doing my layout using HTMLPanel in uiBinder.  </p>
  
  <p>I want to create some whitespace, lets say 70px of height, in several places on the page, to split up the vertical layout of the widgets.  </p>
  
  <p>What is the preferred way to do this?  Using CSS or a panel that isn't visible or some other method?</p>