code: public static MultiMetaDataRequest of(final String... quandlCodes) {
      ArgumentChecker.notNullOrEmpty(quandlCodes, "quandlCodes");
      return new MultiMetaDataRequest(Arrays.asList(quandlCodes));
    }
docs: Factory method to create a meta data request instance.
  
  @param quandlCodes the list of quandl codes for the meta data required (varargs), not null
  @return an instance of the MetaDataRequest for the given quandlCode, not null