Broken implementation (DistributedExecutionCompletionService) of CompletionService in Infinispan

Infinispan has provided an implementation of `java.util.concurrent.CompletionService<V>` `org.infinispan.distexec.DistributedExecutionCompletionService<V>`, However this is broken, as the underlying blocking queue is non-distributed, the moment the node goes down (In which the queue resides), all the content of the nodes would be gone... further this queue is not shared with all the other nodes in the cluster..

And hence a truly distributed blocking queue implementation is required..