Added IndexFlatGenotype to the ADAMMain class.
Fixed a bug in ByteArrayByteAccess.

We were skipping by length (and thus returning 0-length arrays), not by offset.  Oops.
Added support for missing entries "./." in the VCFLineConverter.
Making CombinedFilter serializable.
Adding a constructor to RangeIndex that takes a FileLocator.
Test S3AvroIndexedParquetRDD can pull out a single partition from a multi-rowgroup file.