Allow admins to edit the reservation ahead-of-time language on the membership info pages.

The language on the memberships information page on the portal right now reads, "Reserve up to xxx days in advance." But that only applies to court reservations, and we have different booking windows for our drop-in sessions and other events/classes. I would love to be able to edit this language to make it more clear (or hide it entirely). No need for it to be hard coded.