HDFS-3969. Small bug fixes and improvements for disk locations API. Contributed by Todd Lipcon and Andrew Wang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1572284 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5766. Moved ping messages from TaskAttempts to be at DEBUG level inside the ApplicationMaster log. Contributed by Jian He.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1572380 13f79535-47bb-0310-9956-ffa450edef68
YARN-1301. Added the INFO level log of the non-empty blacklist additions and removals inside ApplicationMasterService. Contributed by Tsuyoshi Ozawa.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1572400 13f79535-47bb-0310-9956-ffa450edef68
YARN-1429. *nix: Allow a way for users to augment classpath of YARN daemons. (Jarek Jarcec Cecho via kasha)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1572405 13f79535-47bb-0310-9956-ffa450edef68