Instead of behaving like a plant and letting you "harvest" butter once in a while they now actually work! To make butter, simply "activate" a butter churn while you have at least one Jug of Milk in your inventory and you get 3 bowls of butter.

This changes the base object, so all churns are affected.

WIP: Activating a cow gives a Jug of Milk. This works every 12 hours on each cow. The work-in-progress part is that there is no prompt when
looking at the cow. Not sure how to fix that.
There also isn't an animation or anything but none of the plants you
harvest from have that either, so it seems fine to me(and I couldn't
actually make the animation).