Move snapshot JIRAs to 2.0.5 section in CHANGES.txt.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1488098 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5176. Add annotation for tagging tasks as responsive to
preemption. Contributed by Carlo Curino, cdouglas


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1488103 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-YAHOO-271-trunk-gd