Add feature flag (#610)

Author: RJV333

config/features.rb

@@ -5,6 +5,7 @@
     in_state :live do
       feature :new_workshop_log, description: "If users should be shown the new unified Workshop Log"
       feature :no_monthly_reports, description: "If the users are not shown the monthly reports"
+      feature :stripe_payments, description: "If users can submit stripe payments for paid events and dues"
       feature :workshop_log_summary, description: "If the workshop log summary should be shown as a separate page"
     end
   end