New player setup menu

Changes the player setup menu to have a 2D grid that can be navigated. Intended to help users select skins when a large amount are loaded.

Demo:

The following WAD is required for the graphics the new screen uses:

extra.wad

Files used to test with:

• https://mb.srb2.org/addons/chengis-character-pack-v22-updated-6-30-22-moonlight-falls-over-crossbell.2069/
• https://mb.srb2.org/addons/ninjis-character-pack.1831/
• https://mb.srb2.org/addons/aarons-char-pack-latest-update-the-iron-giant-hits-the-big-time.2117/