HADOOP-10125. Merging change r1558575 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1558952 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1558948 FIXES: MAPREDUCE-5672. Provide optional RollingFileAppender for container log4j (syslog). Contributed by Gera Shegalov


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1558957 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1558959 FIXES: Moving MR-5672 from bugs to improvements in CHANGES.txt


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1558961 13f79535-47bb-0310-9956-ffa450edef68