Prevent helpers from loading more than one ROM in their life time.
Remove startEmulation method and move its code to startEmulationWithCompletionHandler:.
Remove stopEmulation and move its code to stopEmulationWithCompletionHandler:.
Only allocate an alternate context if one doesn't already exist.
Update submodule references.
Remove setupEmulation and move its code to setupEmulationWithCompletionHandler:, use -runStartUpFrameWithCompletionHandler: instead of running the frame manually.