Pushes messages (or method invocations, if used in conjunctions with MethodCall) to client(s). Used e.g. with PullPushConverter. Rather than blocking the 'pusher', it enqueues messages and uses its own thread to push them one after the other to clients. Thus clients can block the LazyEvaluator, but never the 'real' pusher. Allows the pusher to send non time critical notifications to clients without blocking.
Needs to be refined