HIVE-6466 : Add support for pluggable authentication modules (PAM) in Hive (Vaibhav Gumashta via Thejas Nair)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1571854 13f79535-47bb-0310-9956-ffa450edef68
HIVE-6456: Implement Parquet schema evolution (Brock via Xuefu)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1571877 13f79535-47bb-0310-9956-ffa450edef68