DRILL-375: VarBinary hash function computing hash for entire buffer

Signed-off-by: Jacques Nadeau <jacques@apache.org>
DRILL-376: Create separate DataTunnel for receiving fragment

Signed-off-by: Jacques Nadeau <jacques@apache.org>
DRILL-377: Use BufferedInputStream in SpoolingRawBatchBuffer to improve performance

Signed-off-by: Jacques Nadeau <jacques@apache.org>
DRILL-378: Initialize overLimit field in UnlimitedRawBatchBuffer

Signed-off-by: Jacques Nadeau <jacques@apache.org>
DRILL-366, DRILL-364: Small fixes due to merge issues
Add support for generating optiq planner independent schema plus root for information schema purposes.
Implement storage plugin for INFORMATION_SCHEMA
Update hive to use generated data instead of packaged data. Remove unused test.
Change FileSelection variable name to selection (instead of file, which is not an accurate description)

fix bug when selecting a parquet directory with _metadata file.

handle case where parquet directory does not have _metadata file.
INSTALL.md and packaging fixes given recent merges.
Build fixes for Hive Contrib for clean build
DRILL-396: QuerySubmitter enhancements
Drill 342/238: Clean up Parquet tests.
Update Hive test data generator so that it won't fail on subsequent runs.
DRILL-398: Fix build/packaging issues with storage-hive jars
1. Remove hive-exec dependencies from root pom.xml and move hive-hbase dependency to contrib/storage-hive/pom.xml. Idea is to download all required hive dependencies through storage-hive artifact.
2. In distribution/pom.xml exclude hive-exec jar from storage-hive dependency. Storage-hive jar already contains the shaded hive-exec.
3. In contrib/storage-hive/pom.xml add a target to unpack the classes in storage-hive.jar into contrib/storage-hive/target/classes directory. Unpacking is needed because when you run 'mvn test' from root directory, dependencies within the project (such as protocol or storage-hive) are resolved to target/classes directory instead of jar. This is by design in Maven. If we don't unpack, we get class not found errors for classes in storage-hive.jar while running tests only.
Fix group by, removing aggregate and segment remnants.  Add new simple test queries to make sure parsing isn't broken in future.
Fix binary tree so that more than 2 binary arguments are correctly translated from RexNode.
Update binary function lookup to use lowercase.
DRILL-414: Update root pom.xml so that mapr dependency excludes commons-logging.
DRILL-326: Fixes for merge join allocations
DRILL-346: Move constant expressions to setup.
DRILL-413: Parse issue in QuerySubmitter