Added release notes for aggregations and wan rep
Added release notes for aggregations and wan rep

tombujok/hazelcast,emre-aydin/hazelcast,juanavelez/hazelcast,mdogan/hazelcast,emrahkocaman/hazelcast,tufangorel/hazelcast,emre-aydin/hazelcast,dsukhoroslov/hazelcast,mdogan/hazelcast,tkountis/hazelcast,mesutcelik/hazelcast,dbrimley/hazelcast,dbrimley/hazelcast,tkountis/hazelcast,lmjacksoniii/hazelcast,lmjacksoniii/hazelcast,Donnerbart/hazelcast,Donnerbart/hazelcast,Donnerbart/hazelcast,juanavelez/hazelcast,mesutcelik/hazelcast,mesutcelik/hazelcast,tkountis/hazelcast,dsukhoroslov/hazelcast,tufangorel/hazelcast,emrahkocaman/hazelcast,mdogan/hazelcast,dbrimley/hazelcast,tombujok/hazelcast,emre-aydin/hazelcast,tufangorel/hazelcast