Fix ArrayIndexOutOfBoundsException when parsing Hive timestamp column

When parsing hive timestamp column, `TimestampWritable.getNanos` would cause problem (such as `ArrayIndexOutOfBoundsException`) if the nanos field is not available in byte array. `TimestampWritable` has detection logic to prevent this problem. So this PR uses `TimestampWritable` to parse the bytes of hive timestamp data. Since `TimestampWritable.set()` directly uses given byte data without copying it, the modifying should not add too much cost.