HBASE-10473 Add utility for adorning http Context

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1564936 13f79535-47bb-0310-9956-ffa450edef68
HBASE-10470 Import generates huge log file while importing large amounts of data. (Vasu Mariyala)

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1564950 13f79535-47bb-0310-9956-ffa450edef68