feature: pause screen

[bragerosberg]

Why
The great thing with offline games is the way of which you can play it in the pace you please. Currently there is nothing possible to control the pace between start to finish, whenever you have begun it is fully on! 🏃 🏁

What
An option to pause the game, wether it would be a simple freeze when pressing a button such as P, or a potential pause screen one often can meet when pressing Esc. It is up for decision at the time this issue will be handled. Currently I see both as reasonable approaches that could both delivery quite some value.