envify react in production

Made the mistake to include the development build of react in the production build. Fixed by setting process.env manually to production in makewebpackconfig.js

Thx to @gaearon for https://twitter.com/dan_abramov/status/592692202335301636

Author: mxstbr

makewebpackconfig.js

@@ -37,7 +37,12 @@ module.exports = function(options) {
         },
         inject: true // inject all files that are generated by webpack, e.g. bundle.js, main.css with the correct HTML tags
       }),
-      new ExtractTextPlugin("css/main.css")
+      new ExtractTextPlugin("css/main.css"),
+      new webpack.DefinePlugin({
+        "process.env": {
+          NODE_ENV: JSON.stringify("production")
+        }
+      })
     ];
 
   // If app is in development