Dark Menus

Adds one row to the sMods settings category:

• Dark menus — a dark palette for Big Walk's paper menu panels (on by default), including a dark main menu, a white cursor with a drop shadow, and a dark backing behind the join-password prompt.

Menus are re-themed from each element's recorded ORIGINAL colour, so switching the theme off restores the game's exact look.

Big Walk has no anti-cheat, and this mod doesn't change how the game plays.