graphics/gowall: New port: Versatile tool to process images

Gowall is a versatile tool to convert an image (specifically a wallpaper)
to any color-scheme and/or pallete you like! It also offers a bunch of
image processing features like image to pixel art, image upscaling, and
color palette extraction.

WWW: https://github.com/Achno/gowall

PR: 282799
Reported by: Yusuf Yaman <nxjoseph@protonmail.com> (new maintainer)