MAPREDUCE-5062. Fix MR AM to read max-retries from the RM. Contributed by Zhijie Shen.
svn merge --ignore-ancestry -c 1460923 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1460924 13f79535-47bb-0310-9956-ffa450edef68
Merge -c 1460954 from trunk to branch-2 for YARN-498. Unmanaged AM launcher does not set various constants in env for an AM, also does not handle failed AMs properly (Hitesh Shah via bikas)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1460955 13f79535-47bb-0310-9956-ffa450edef68
YARN-469. Make scheduling mode in FS pluggable. (kkambatl via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1460962 13f79535-47bb-0310-9956-ffa450edef68