title: smartgwt browser history
body: <p>is there a way in smartgwt to go back in history?</p>
  
  <p>E.g. I have an page with a button which does a Ajax page change of the current page to another. And on this new page there should be a button to return back to the previous page?</p>
  
  <p>Can this be done with smartGWT? or do I have to make a new Ajax call to switch back to the previous page?</p>