This involves a large amount of change in test scene setup code to allow test scenes to share shared modules
SetupScene is now an instance method that requires an instantiation of SceneHelpers, though other SceneHelpers methods are still static
May split these out into separate classes in the future.
While implementing this, a bug was fixed in scene setup helpers where module RegionLoaded() was called immediately after AddRegion() instead of waiting for all AddRegions() to complete.
Also, XmlRpcGroupsModule non-message functionality will now work without a message transfer module (as indicated in the comments but with a contradictory implementation)
