Adding some Assertion

For form validation
Adding a view to watch one article
Updating DefaultController

Adding Afficher Controler
Generating a 404 Response after giving a fake id
Adding the route to afficher
Adding Editer function

Adding editerAction in the DefaultControler
Creating the view with the form
Passing the Id when the update form is submitted
Separating the code

Creating a file for the header, footer and Article_content
Including them on index.html.twig or on affiche.html.twig
And on base.html.twig