Provide JMX operation which shows the numberOfEntries in the entire dist-cache

The Infinispan statistics component only shows the 'numberOfEntries' in a particular node, including entries of which the node is not the primary owner (basically, doing a sum of this value of all the cluster members gives you (numberOfEntries * numOwners). The 'cache.keySet()' method does return the entire keyset, and thus you can calculate the numberOfEntries in the cache, but this requires writing custom code in a cache client. It would be nice if Infinispan would provide a JMX operation which is able to show the number of entries in the entire dist-cache cluster.