…tup page. (Needs a better fix).
…w is now separate. Add `POST` check for setup page, and call `gocardless_admin_update`.
…ttings and subscriptions.
…Cardless API Keys. Add id to sandbox label.
… is specified in GoCardless developer settings (instead of loading on every page). Need to look into specifying custom complete pages for other subscriptions, therefore keeping the wp_footer hook in for now.