Allow a stripe plan to be superseded

If a plan has a direct corrolary, show that one as the selected plan
instead of showing the plan as deprecated even though it has the same
details

static/js/services/plan-service.js

@@ -148,6 +148,13 @@ function(KeyService, UserService, CookieService, ApiService, Features, Config) {
     });
   };
 
+  planService.getPlanImmediately = function(planId) {
+    // Get the plan by name, without bothering to check if the plans are loaded.
+    // This method will return undefined if planId is undefined or null, or if
+    // the planDict has not yet been loaded.
+    return planDict[planId];
+  };
+
   planService.getMinimumPlan = function(privateCount, isBusiness, callback) {
     planService.getPlans(function(plans) {
       for (var i = 0; i < plans.length; i++) {