Message Priority in Akka

http://blog.knoldus.com/2014/03/13/how-to-create-a-priority-based-mailbox-for-an-actor/

http://doc.akka.io/docs/akka/2.4.1/java/mailboxes.html

http://stackoverflow.com/questions/15337329/akka-actor-post-a-message-to-head-of-the-mailbox