add method
Implementation
@override
Future<int?> add() {
if (!initialized) throw ArgumentError(AbstractDao.C_MUST_INIT);
ConfigurationDto configurationDto = ConfigurationDto.field(trDto, defaults);
return configurationDao.addConfiguration(
configurationDto.subset,
configurationDto.warden,
configurationDto.configuration_name,
configurationDto.ordinal,
configurationDto.value_number,
configurationDto.value_string);
}