Support resolving ORC file columns by names

Currently we resolve ORC file columns by indices. We should provide an query option like PARQUET_FALLBACK_SCHEMA_RESOLUTION for Parquet (IMPALA-2835), to resolve ORC file columns by names.

Note that Hive only writes column names to ORC files after Hive-2.x (HIVE-4243). For older versions of Hive, the column names in ORC files are something like _col0, _col1,....,_col99. So this feature is only required when deployed with Hive 2+.