YARN-1170. YARN & MapReduce proto definitions fixed to specify protobuf package as hadoop.yarn and hadoop.mapreduce respectively. Contibuted by Binglin Chang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1523652 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5493. Cleanup in-memory & on-disk segments to prevent leak on shuffle completion. Contributed by Jason Lowe.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1523660 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd