Add missing YARN-1471 to the CHANGES.txt

hadoop-yarn-project/CHANGES.txt

@@ -15,6 +15,9 @@ Trunk - Unreleased
     YARN-524 TestYarnVersionInfo failing if generated properties doesn't
     include an SVN URL. (stevel)
 
+    YARN-1471. The SLS simulator is not running the preemption policy 
+    for CapacityScheduler (Carlo Curino via cdouglas)
+
     YARN-2216 TestRMApplicationHistoryWriter sometimes fails in trunk.
     (Zhijie Shen via xgong)