Add option to hide with game UI

[Ezio Mariani]

I'm aware there's a setting to hide the chat, but this requires a dedicated key and won't work on gamepad. Oftentimes when I'm playing COTD, I want to hide the game UI so I can fully focus, but Better Chat still shows and is a distraction.

[Marijn Regterschot]

I would also love for this feature to be implemented.

[Ezio Mariani]

I've already done the work, just forgot to make a new PR since the last one messed up