/**
* Clean out a cache group as named by param.
* If no param is passed clean all cache groups.
*
* @param String $group
*/
public function clean($group = '')
{
$conf = JFactory::getConfig();
//Clear cache in fontend
$path = $conf->get('cache_path', JPATH_ROOT . DS . 'cache');
$cache = PlgIceSpeedHelper::getCache($path);
$cache->clean($group);
//Clear cache in backend
$path = JPATH_ROOT . DS . 'administrator' . DS . 'cache';
$cache = PlgIceSpeedHelper::getCache($path);
$cache->clean($group);
}