HDFS-4618. Default transaction interval for checkpoints is too low. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1461784 13f79535-47bb-0310-9956-ffa450edef68
YARN-209. Fix CapacityScheduler to trigger application-activation when the cluster capacity changes. Contributed by Zhijie Shen.
svn merge --ignore-ancestry -c 1461773 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1461790 13f79535-47bb-0310-9956-ffa450edef68