Added test server

Run npm start for demo on localhost

utils/server.js

@@ -0,0 +1,12 @@
+const express = require('express')
+const app = express()
+
+// app.get('/hello', (req, res) => res.send('Hello World!'))
+
+app.use('/css', express.static('css'))
+app.use('/src', express.static('src'))
+app.use('/external', express.static('external'))
+app.use('/demo', express.static('demo'))
+app.use('/', express.static('demo'))
+
+app.listen(80, () => console.log('Example app listening on port 80!'))