Add frontend to be served by backend.

frontend/src/index.js

@@ -0,0 +1,7 @@
+console.log('Hello world! ++++++');
+
+document.getElementById('content').innerHTML = `
+    <div>
+        <h1>Hello world!</h1>
+    </div>
+`;

frontend/webpack.config.js

@@ -0,0 +1,24 @@
+const webpack = require("webpack");
+const path = require("path");
+const UglifyJSPlugin = require("uglifyjs-webpack-plugin");
+
+let config = {
+    entry: "./frontend/src/index.js",
+    output: {
+        path: path.resolve(__dirname, "../backend/public"),
+        filename: "bundle.js"
+    },
+    devServer: {
+        contentBase: path.resolve(__dirname, "../backend/public"),
+        historyApiFallback: true,
+        inline: true,
+        open: true,
+        hot: true
+    },
+    plugins: [
+        new UglifyJSPlugin(),
+        new webpack.SourceMapDevToolPlugin({})
+    ],
+    devtool: "eval-source-map"
+}
+module.exports = config;