Krastorio 2's best tier of floor tile can be made in light and dark versions, but they're not interchangable... for some reason. This fixes that by adding a recipe to swap em. I wanted to add placeable_by to both types, as to make them completely interchangable in blueprints, but couldn't figure it out, so feel free to add that in a comment or something and I'll update it (if I get notified).