work around invalid es6 code generated

ref rescript-lang/rescript#2456

Author: cyberhuman

src/Express.re

@@ -1,3 +1,5 @@
+[%%raw "import Express from 'express'"];
+
 type complete;
 
 module Error = {
@@ -396,8 +398,8 @@ module Middleware = {
     "limit": Js.nullable(int),
     "parameterLimit": Js.nullable(int)
   };
-  [@bs.module "express"] [@bs.val] external json_ : jsonOptions => t = "json";
-  [@bs.module "express"] [@bs.val] external urlencoded_ : urlEncodedOptions => t = "urlencoded";
+  [@bs.scope "Express"] [@bs.val] external json_ : jsonOptions => t = "json";
+  [@bs.scope "Express"] [@bs.val] external urlencoded_ : urlEncodedOptions => t = "urlencoded";
   let json = (~inflate=true, ~strict=true, ~limit=?, ()) =>
     json_({
       "inflate": inflate |> Js.Boolean.to_js_boolean,
@@ -549,7 +551,7 @@ module Router = {
     .
     "caseSensitive": Js.boolean, "mergeParams": Js.boolean, "strict": Js.boolean
   };
-  [@bs.module "express"] [@bs.val] external make_ : routerArgs => t = "Router";
+  [@bs.scope "Express"] [@bs.val] external make_ : routerArgs => t = "Router";
   let make = (~caseSensitive=false, ~mergeParams=false, ~strict=false, ()) =>
     make_({
       "caseSensitive": caseSensitive |> Js.Boolean.to_js_boolean,
@@ -571,7 +573,8 @@ module App = {
   let useRouter = (app, router) => Router.asMiddleware(router) |> use(app);
   let useRouterOnPath = (app, ~path, router) =>
     Router.asMiddleware(router) |> useOnPath(app, ~path);
-  [@bs.module] external make : unit => t = "express";
+  [@bs.val] external make : unit => t = "Express";
+  let make = make;
 
   /*** [make ()] creates an instance of the App class. */
   external asMiddleware : t => Middleware.t = "%identity";
@@ -595,9 +598,9 @@ module Static = {
   [@bs.set] external etag : (options, Js.boolean) => unit = "";
   /* ... add all the other options */
   type t;
-  [@bs.module "express"] external make : (string, options) => t = "static";
+  [@bs.scope "Express"] [@bs.val] external make : (string, options) => t = "static";
 
   /*** [make directory] creates a static middleware for [directory] */
   external asMiddleware : t => Middleware.t = "%identity";
   /*** [asMiddleware static] casts [static] to a Middleware type */
-};
+};