Update readme

Author: jeroenheijmans

README.md

@@ -2,11 +2,26 @@
 
 This repository shows a basic Angular CLI application with [the `angular-oauth2-oidc` library](https://github.com/manfredsteyer/angular-oauth2-oidc) and Angular AuthGuards.
 
+## Features
+
+This demonstrates:
+
+- Use of **the Implicit Flow**
+- Modules (core, shared, and two feature modules)
+- An auth guard that forces you to login when navigating to protected routes
+- An auth guard that just prevents you from navigating to protected routes
+- Asynchronous loading of login information (and thus async auth guards)
+- Using `localStorage` for storing tokens (use at your own risk!)
+- Loading IDS details from its discovery document
+- Trying silent refresh on app startup before potientially starting a login flow
+- OpenID's external logout features
+
+Most interesting features can be found in [the core module](./src/app/core).
+
 ## Usage
 
-This repository has been scaffolded with the Angular 5 CLI.
-Make sure you have the CLI globally installed.
-Then:
+This repository has been scaffolded with the Angular 5 CLI, then later upgraded to newer versions of the Angular CLI.
+To use the repository:
 
 1. Clone this repository
 1. Run `npm install` to get the dependencies