/**
  * set calendar component property tzname
  *
  * @author Kjell-Inge Gustafsson, kigkonsult <*****@*****.**>
  * @since 2.16.21 - 2013-06-23
  * @param string   $value
  * @param array    $params
  * @param integer  $index
  * @uses calendarComponent::_createParams()
  * @uses calendarComponent::$tzname
  * @uses iCalUtilityFunctions::_setMval()
  * @return bool
  */
 function setTzname($value, $params = FALSE, $index = FALSE)
 {
     if (empty($value)) {
         if ($this->getConfig('allowEmpty')) {
             $value = '';
         } else {
             return FALSE;
         }
     }
     iCalUtilityFunctions::_setMval($this->tzname, $value, $params, FALSE, $index);
     return TRUE;
 }