setting time to live of result set caches as their time to idle. When time to live is 0 it means entries are eternal and we do not want this.
ResultSetService exposes a new ResultSet property that is used by the Counting RS Listener to not close the result set if the underlying result set is an open Push Result set.
explicitely setting the push rs cache to overflow on disk
ehcache properties for push result set are properties
introduced synchronized in size() in order to provide thread safeness.