HIVE-7535: Make use of number of nulls column statistics in filter rule (Prasanth J via Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1614504 13f79535-47bb-0310-9956-ffa450edef68
HIVE-7536: Make use of decimal column statistics in statistics annotation (Prasanth J via Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1614505 13f79535-47bb-0310-9956-ffa450edef68