Convert angular-addressbook into exercise

[Auenc]

The angular-addressbook is an exemplar for the second exercise in Angular. The idea behind the exercise is to introduce the concept of Modules, forms, and routing.

What needs to be done:

• [x] Create the learning objectives for the exercise
• [x] Add instructions for setting up the exercise
• [x] Come up with requirements that will bring the student to the finished exercise.

[Auenc]

Here is the link to the exercise version: https://github.com/boolean-uk/angular-address-book

[Auenc]

This needs to be updated to use ReactiveForms