Add examples to the documentation

[lastmjs]

Think of the best way to add code examples.

[lastmjs]

We need to add examples of most of the common Express use-cases:

• Creating an app and listening on a port
• Adding a generic middleware (app.use)
• Adding a middleware with a method (app.all, app.get, app.post, etc.)
• Doing configurations (all other app or express method calls that require a config element)
• Adding a middleware with a method to router: router.method (router.all, router.get, router.post, etc.)
• Adding generic middleware to router (router.use)
• router.route
• Configuring router (router.param)
• app.route and router.route

To summarize, show everything that you can do. app middleware, router middleware, and app and router configuration, properties, and methods