[FR] Option to mute all sounds

[OptionalM]

In the intro there's a button labelled "Mute", I'm not sure if that's supposed to only mute the intro sound, or all sounds, but it would be great to have an option to mute all game sounds.

[SoltauFintel]

Thanks for playing the game. You are not the first to have this wish. Development is paused because #23.