code: public static ResourceRecordSet<SPFData> spf(String name, String spfdata) {
      return new SPFBuilder().name(name).add(spfdata).build();
    }
docs: creates spf set of spf single {@link denominator.model.rdata.SPFData SPF} record for the
  specified name.
  
  @param name    ex. {@code denominator.io.}
  @param spfdata ex. {@code v=spf1 a mx -all}