Reverting MAPREDUCE-5028 (commit 1457918)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1458433 13f79535-47bb-0310-9956-ffa450edef68
YARN-200. yarn log does not output all needed information, and is in a binary format. Contributed by Ravi Prakash


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1458466 13f79535-47bb-0310-9956-ffa450edef68