code: protected String addCommonContextVars(ModelMap model, HttpServletRequest request) 
  	{
  		return addCommonContextVars(model, request, null, null);
  	}
docs: sets common context variables<br>
  <ul>
  <li>contentPage</li>
  <li>activeMenuName</li>
  <li>activeMenu</li>
  <li>rootContext</li>
  <li></li>
  </ul>
  
  @param model
  @param request
  @return