HIVE-8003 : CBO: Handle Literal casting, Restrict CBO to select queries, Translate Strings, Optiq Log (Laljo John Pullokkaran, reviewed by Sergey Shelukhin)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/cbo@1622813 13f79535-47bb-0310-9956-ffa450edef68