Updates to "new scene" logic.
When an event is running, any subsequently pushed non-scenes are saved to mPreviousScene (and are picked up after the scene is finished).  New scenes overwrite the currently running one (as before)
Includes updates to relevant tests
Rename IsDormant -> IsEnabled and change parity
Remove IsSynchronised and IsEvent on amBXScene in favour of a Scene Type enum
Update xml files to use new Scene Type
Rewrite the server to use a more passive approach to updating.  Some limitations:
* Some tests fail
* Some issues with running events etc.  Not fully tested!
Remove 1-argument constructors for SceneHandler and fix tests
Move SceneType member variables to a SceneStatus class
Move starting conductors into SceneUpdateHandler.
tweaks
Add new Update method that supercedes the UpdateActors and KickOffConductors methods
Remove deprecated methods (note: will not build as methods are missing)
Rewrite ConductorBase Run method to keep track of whether or not it's running
Add the missing private methods and add missing breaks
Allow the ability to choose when the SceneHandler is enabled
Add Enable... methods to the ComponentManager to enable SceneHandlers
Break up the Update method to non-event-complete and event-complete cases.  Throws if something unexpected happens
Use the new SceneUpdateHandler everywhere
Update Enable methods to also kick off the conductors if it makes sense to do so (by looking at IsRunning)
Bug fixes
Update tests