Livelier gathering spots

• Gathering spots and town workshops now move on their own, and come alive while a cat works them: mice bolt for their burrows, herbs shed petals, a float bobs on the pond, bark curls fly off, rock chips and sparks fly, fires roar and the loom's shuttle races.
• You can now see when other cats are skilling: they take the working pose, and their spot livens up too.