static boolean[] genIncludedColumns(TypeDescription readerSchema,
                                             Configuration conf) {
     if (!ColumnProjectionUtils.isReadAllColumns(conf)) {
      List<Integer> included = ColumnProjectionUtils.getReadColumnIDs(conf);
      return genIncludedColumns(readerSchema, included);
    } else {
      return null;
    }
  }
Take the configuration and figure out which columns we need to include.
@param readerSchema the types for the reader
@param conf the configuration
ql/src/java/org/apache/hadoop/hive/ql/io/orc/OrcInputFormat.java