/**
  * Save System User
  * 
  * @param SystemUser $systemUser 
  * @return void
  */
 public function saveSystemUser(SystemUser $systemUser)
 {
     try {
         $systemUser->clearRelated('Employee');
         $systemUser->save();
         return $systemUser;
     } catch (Exception $e) {
         throw new DaoException($e->getMessage(), $e->getCode(), $e);
     }
 }