/**
  * Initialise the {@link SiteNavigation} object
  *
  * The {@link SiteNavigation} object implements a Singleton pattern, and controls
  * the access to navigation items, as well as the process of printing them to the
  * output.
  * @param force_reload - reload the navigation item even if one is already registered
  */
 public function siteNavigationInit($force_reload = false)
 {
     if (!SiteNavigation::ready() || $force_reload) {
         $ret = SiteNavigation::init($this->user->getHandlerTree());
     } else {
         $ret = SiteNavigation::current();
     }
     return $ret;
 }
 /**
  * Return the current SiteNavigation object for this site
  * @param supress_error - default 'false', set true if no error
  *                        should be generated if a SiteNavigation
  *                        object cannot be found
  * @access public
  * @throws Exception - in the case that no site navigation is registered
  */
 function getSiteNavigation()
 {
     if (!($ret = SiteNavigation::current())) {
         throw new Exception('Unable to find registered SiteNavigation object in getNavigation, display.class.inc');
     }
     return $ret;
 }