Tower Kelp changes

[Mariolo]

The current orehul + tower kelp loop is way too simple for how much you get out of it. There are no refinement processes involved and can be scaled as much as you want. While there are also other closed loops that produce resources, these are all more complex and often involve processing resources into others.

My suggested nerf is to add an irrigation requirement to tower kelp. The obvious choice is polluted water, but if we want to get creative it could be mucin. This makes it need an external input and puts a limit on how many tower kelp you can plant. It'd still be very good but more on par with other critters.