When Dungeons Arise

Reworked Mushroom Villages to be less cramped.

Implemented changes to structure sets to make them less likely to collide. Structures were internally grouped in 'minor' and 'major' structures, which cannot generate next to each other (minor structures always have a gap between them).

Loot tables were changed or nerfed in a few structures, including ships, mushroom villages, illager forts, etc.

Structures generate more sparsely.

Fixed mining system loot tables - treasure and basic loot tables have been switched.

Fixed exploration maps appearing as empty maps on most structures.

Added more exploration maps (i.e.: abandoned_temple -> mining_system).

Removed Small Prairie Houses.