HIVE-9113 : Explain on query failed with NPE (Navis reviewed by Szehon Ho)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1646390 13f79535-47bb-0310-9956-ffa450edef68
HIVE-8848 : data loading from text files or text file processing does not handle nulls correctly (Navis reviewed by Sergey Shelukhin)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1646391 13f79535-47bb-0310-9956-ffa450edef68
HIVE-9096 : GenericUDF may be left unclosed in PartitionPrune#visitCall() (Niranjan Singh via Navis)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1646394 13f79535-47bb-0310-9956-ffa450edef68