HIVE-6077: Fixing a couple of orc unit tests on tez (Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/tez@1552480 13f79535-47bb-0310-9956-ffa450edef68
HIVE-6078: Choosing conditional task for merging files is not deterministic in tez (Vikram Dixit K via Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/tez@1552482 13f79535-47bb-0310-9956-ffa450edef68
HIVE-6079: Hadoop 1 tests fail in tez branch (Vikram Dixit K via Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/tez@1552483 13f79535-47bb-0310-9956-ffa450edef68
HIVE-6081: Dag utils in tez has incorrect dependency on Hadoop20 shims (Vikram Dixit K via Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/tez@1552485 13f79535-47bb-0310-9956-ffa450edef68