Add a new section of "support plants"

These could be plants that aren't really able to be evolved, such as Lily pad, gravebuster, or cherry bomb. If they had their own section, they wouldn't be lumped in with all the other tier 1 plants, thus removing confusion of them being able to be evolved or not. If you do add support plants, it might be smart to include a 6th seed slot. If the plant would provide great benefit to the level, but wouldn't have the utility to be evolved, then players might be less encouraged to bring them in any level.