Editor: Fix the command line as a result of removing some deprecated functions.
Fix a bug in Game::LoadGameState() where the file was being opened in write mode instead of read mode.
Fix a bug when reading a string from the generic game state manager.
Disable the state stack when deserializing a scene.
Add a method to the generic game state manager for retrieving a pointer to a data structure containing information about the difference between a base scene and it's saved state.
Update the sandbox to use the new game state system.
Disable the state stack when destructing a Scene object.

If we leave the state stack enabled, it'll post delete commands to the staging
area which isn't really useful during destruction.
Fix a few issues regarding updating of the scene state in the sandbox's game state manager.
Early support for saving/loading game state date through the scripting environment when using the default game state manager.