This prevents a crash later when we refer to properties
of the plan object, which can end up being `null` when
the `planCode` is either missing, or not a valid code.
- always show the manage button if you are the group owne
- only show the recurly subscription part if you are the subscription owner
- always try and loop through groups you can leave
- get all accounts does get all of them by looping through all pages
- creating coupons requires which plan the coupon is for
- fixed the total price shown to people so it includes tax
