HIVE-6125: Tez: Refactoring changes (Gunther Hagleitner, reviewed by Thejas M Nair)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1556041 13f79535-47bb-0310-9956-ffa450edef68
HIVE-5829: Rewrite Trim and Pad UDFs based on GenericUDF (Mohammad Islam via cws)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1556125 13f79535-47bb-0310-9956-ffa450edef68
HIVE-5946 - DDL authorization task factory should be better tested (Brock reviewed by Thejas)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1556253 13f79535-47bb-0310-9956-ffa450edef68
HIVE-2599 - Support Composit/Compound Keys with HBaseStorageHandler (Swarnim Kulkarni via Brock Noland)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1556266 13f79535-47bb-0310-9956-ffa450edef68
HIVE-6105: LongWritable.compareTo needs shimming (Navis vis Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1556309 13f79535-47bb-0310-9956-ffa450edef68
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