Unity editor gets stuck after MPF crashes

[arthurkehrwald]

If MPF crashes for whatever reason (e.g. invalid config), the Unity editor will get stuck on domain reload next time play mode is entered.
To reproduce:

1. Enter play mode with an invalid MPF config (MPF will crash immediately)
2. Exit play mode
3. Attempt to enter play mode again. The domain reload will never finish. You are now stuck :(

[arthurkehrwald]

I found the line it gets stuck on: _client.Quit(new QuitRequest()); in method MpfClient.Shutdown

[arthurkehrwald]

Fixed in #31