HIVE-5731 : Use new GenericUDF instead of basic UDF for UDFDate* classes (Mohammad Islam via Ashutosh Chauhan)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1553426 13f79535-47bb-0310-9956-ffa450edef68
HIVE-5891 : Alias conflict when merging multiple mapjoin tasks into their common child mapred task (Sun Rui via Yin Huai)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1553427 13f79535-47bb-0310-9956-ffa450edef68
Merge latest trunk into branch. (Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/tez@1553448 13f79535-47bb-0310-9956-ffa450edef68