code: public static Reader reader(Format type, InputStream in, Map<String, ReadHandler<?, ?>> customHandlers) {
          return reader(type, in, customHandlers, null);
      }
docs: Creates a reader instance.
  @param type the format to read in
  @param in the input stream to read from
  @param customHandlers a map of custom ReadHandlers to use in addition
  or in place of the default ReadHandlers
  @return a reader