YARN-1085. Modified YARN and MR2 web-apps to do HTTP authentication in secure setup with kerberos. Contributed by Omkar Vinit Joshi.
svn merge --ignore-ancestry -c 1517101 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1517102 13f79535-47bb-0310-9956-ffa450edef68