Add Ultica tileset demo to mainline

[I-am-Erk]

Summary

SUMMARY: Content "Adds the Ultica tileset to mainline, in demo form"

Description of change

Ooh, it's the release demo of Ultica, bugfixed and ready for its first mainlining!

Ultica is a community-driven tileset aiming for a realistic style with 8-bit inspired graphics, similar to classic games like Ultima VII. Although still missing a lot of tiles, it has now passed the threshold where I'd call it "playable". Still, be aware, like many of the older tilesets in the repo, there are many holes in this. On the other hand, unlike the older tilesets, we're adding scores of new tiles in an ever-encroaching effort to catch up. You too can join this effort! Check out the discord, or the #graphics-and-sound room on the official discord, or just start PRing changes at https://github.com/I-am-Erk/CDDA-Tilesets/ if you're heckin' confident.

Now with far fewer fillers, but be ready for a few semicolons!

Bonus: basic winter filler art!

If you have any concerns with prominent missing art or any glitches, please log them on the discord

Additional Context

Vehicles look terrible by intention. This is my protest until we can get a better vehicle drawing engine.

[ScampsAdams]

Excellent work! Congratulations on mainlining!
Shadows rotating with sprites are striking, though... Started dreaming of dynamic shadows, for example invisible in cloudy weather...