Fixed some things with Mattern algorithm. I changed it after

testing mattern by writing a small program that links with the warped
library. I only tested it on a single node and two nodes.
Removed send queue from TimeWarpCommunicationManager

and added a remote event queue to TimeWarpEventDispatcher.
This will make it easier to add the gvt info(mattern color)
to the event messages and update mattern state without
involving the worker threads. Also added methods for worker threads
to enqueue an event and to send all events.
Very minor change
Fixed unit tests