change engine mount point and base path in jsapp

assets/javascripts/discourse/controllers/s-index.js.es6

@@ -3,7 +3,7 @@ import { ajax } from "discourse/lib/ajax";
 export default Ember.Controller.extend({
   actions: {
     stripePaymentHandler(data) {
-      return ajax("/patrons/patrons", {
+      return ajax("/s/patrons", {
         data,
         method: "post"
       }).catch(() => {

assets/javascripts/discourse/controllers/s-subscribe-show.js.es6

@@ -25,7 +25,7 @@ export default Ember.Controller.extend({
             source: result.token.id
           };
 
-          return ajax("/patrons/customers", {
+          return ajax("/s/customers", {
             method: "post",
             data: customerData
           }).then(customer => {