Add user model through devise. Add some basic layout. Start testing in travis.

config/webpack/environment.js

@@ -1,3 +1,17 @@
 const { environment } = require('@rails/webpacker')
 
+const webpack = require("webpack");
+
+// Add an additional plugin of your choosing : ProvidePlugin
+environment.plugins.prepend(
+    "Provide",
+    new webpack.ProvidePlugin({
+        $: "jquery",
+        jQuery: "jquery",
+        jquery: "jquery",
+        "window.Tether": "tether",
+        Popper: ["popper.js", "default"] // for Bootstrap 4
+    })
+);
+
 module.exports = environment