Log Message:
stone-soup[-sdl]: Update to 0.31.0

Highlights

- New skill and background: Shapeshifters, using Talismans to change forms.
- New skill and background: Alchemists, melding Poison Magic and Transmutation.
- A variety of exciting new spells for sorcerers and sword-slingers alike.
- Many dangerous new monsters, from the early Dungeon to the Realm of Zot.
- Major changes to many species.