CDK-591: Detect the correct package for the Parquet SerDe to work with Hive 0.13
CDK-580: Move partitioning helper methods to CrunchDatasets.
CDK-203: Add sync to DatasetWriters.

For Avro and CSV FileSystem appenders, sync is implemented as flush
followed by hsync. For Parquet, there is no implementation because there
is no way to flush or sync parquet files. For HBase, sync calls flush.

This adds tests for CSV and Avro sync behavior, which doesn't currently
work for the local FS, but does for HDFS.
CDK-599: Added missing @since tags

Closes #180.
CDK-583: Fix non-string types with id partitioner.

The conversion from path to StorageKey was incorrectly using the
FieldPartitioner#getType() method. The fix is to use
SchemaUtil.getPartitionType(), which will use the type from the schema
for identity partitioners rather than Object.class which results in no
conversion.

Most of the changes are to add a Schema to the PathConversion class and
update its tests.
CDK-597: Release notes for 0.16.0
CDK-597: prepare release release-0.16.0
CDK-597: prepare for next development iteration
CDK-597: Update jdiff files.
CDK-601: Fix link to Spark example.