HDFS-5110. Mreging change r1515624 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1515630 13f79535-47bb-0310-9956-ffa450edef68
YARN-1006. Fixed broken rendering in the Nodes list web page on the RM web UI. Contributed by Xuan Gong.
svn merge --ignore-ancestry -c 1515629 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1515631 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-9860. Remove class HackedKeytab and HackedKeytabEncoder from hadoop-minikdc once jira DIRSERVER-1882 solved. (ywskycn via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1515653 13f79535-47bb-0310-9956-ffa450edef68