[Balance] The kiln has too many spaces

[donoya]

I think the kiln has too many slots for doing recipes. I think it should be reduced to around 4-6. As it currently is, my colony uses my kiln a lot, but I've been perfectly fine just using the one kiln all the way through the middle ages tech tree (I started with tribal and I'm currently over halfway through researching all of the medieval technologies). I think it needs to be nerfed to incentivize building more than one kiln.