Update: ServerDemoPlayer - Only maintain entities from demo stream - Destroys any entities that server decides to create, if they were not part of demo stream - Reserve a 100k network IDs when playing a demo to avoid ID clashes - Refactored message logging when playing back demos Although not robust, this allows us to simulate a core set of functionality. Will need massaging to expand further. Tests: played back 4 separate Craggy demos - all played back properly.