svn merge -c 1442824 from trunk for HDFS-4468.  Use the new StringUtils methods added by HADOOP-9252 and fix TestHDFSCLI and TestQuota.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1442825 13f79535-47bb-0310-9956-ffa450edef68