MAPREDUCE-5672. Provide optional RollingFileAppender for container log4j (syslog). Contributed by Gera Shegalov


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1558948 13f79535-47bb-0310-9956-ffa450edef68
backported HADOOP-10125 to branch2, update CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1558953 13f79535-47bb-0310-9956-ffa450edef68
Moving MR-5672 from bugs to improvements in CHANGES.txt


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1558959 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5784. Reserve space in edit log header and fsimage header for feature flag section (cmccabe)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1558974 13f79535-47bb-0310-9956-ffa450edef68