Add MaterializeCSS styles (#1)

## Changes
* Adds the [AssetPack](https://metacpan.org/pod/Mojolicious::Plugin::AssetPack) Mojolicious plugin
* Adds the [MaterializeCSS](https://www.npmjs.com/package/materialize-css) Node package
* Applies styles to app

Reviewed-on: #1

mojo_app/package-lock.json

@@ -0,0 +1,18 @@
+{
+  "name": "mojo_app",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "materialize-css": "^1.0.0"
+      }
+    },
+    "node_modules/materialize-css": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/materialize-css/-/materialize-css-1.0.0.tgz",
+      "integrity": "sha512-4/oecXl8y/1i8RDZvyvwAICyqwNoKU4or5uf8uoAd74k76KzZ0Llym4zhJ5lLNUskcqjO0AuMcvNyDkpz8Z6zw==",
+      "license": "MIT"
+    }
+  }
+}