function for the 'ChangePolicy' parameter.
cf.WriteDouble("Free", td.tariffConf.free);
cf.WriteString("TraffType", TARIFF::TraffTypeToString(td.tariffConf.traffType));
cf.WriteString("Period", TARIFF::PeriodToString(td.tariffConf.period));
cf.WriteDouble("Free", td.tariffConf.free);
cf.WriteString("TraffType", TARIFF::TraffTypeToString(td.tariffConf.traffType));
cf.WriteString("Period", TARIFF::PeriodToString(td.tariffConf.period));
+ cf.WriteString("ChangePolicy", TARIFF::ChangePolicyToString(td.tariffConf.changePolicy));