hazelcast config: put if absent when merging

Change-Id: Id39deafc7616b2d85d570bc6e62bb0331a04a3f6
diff --git a/tools/package/etc/hazelcast.xml b/tools/package/etc/hazelcast.xml
index b950768..b92a793 100644
--- a/tools/package/etc/hazelcast.xml
+++ b/tools/package/etc/hazelcast.xml
@@ -176,7 +176,7 @@
             com.hazelcast.map.merge.HigherHitsMapMergePolicy ; entry with the higher hits wins.
             com.hazelcast.map.merge.LatestUpdateMapMergePolicy ; entry with the latest update wins.
         -->
-        <merge-policy>com.hazelcast.map.merge.PassThroughMergePolicy</merge-policy>
+        <merge-policy>com.hazelcast.map.merge.PutIfAbsentMapMergePolicy</merge-policy>
 
     </map>