[NEEDS TESTING] Move joystick configuration settings into general settings window.

No functionality is changed, I've just merged the Joystick Config window in with the general settings window.

Only downside to this is that the joystick listener thread now runs as soon as the settings window is opened. Really this should be tied to the on/off button in the settings window, which I will add in another commit or PR.

I do not have any joysticks available to me at this time, so this requires someone to actually check that functionality is preserved. Do not merge until someone else tests and confirms joysticks still work with this patch.