code: @Override
      public Response sendToNTS(String CorpNum, MgtKeyType KeyType, String MgtKey)
              throws PopbillException {
          return sendToNTS(CorpNum, KeyType, MgtKey, null);
      }
docs: /* (non-Javadoc)
  @see com.popbill.api.TaxinvoiceService#sendToNTS(java.lang.String, com.popbill.api.taxinvoice.MgtKeyType, java.lang.String)