Update README with lessons details

Here is the README from [foxted/larabook](https://github.com/foxted/larabook) with all the links to each lesson in case you want to include it in your repo. I also gave you access to the [foxted/larabook](https://github.com/foxted/larabook) repo in case you want to use all the tags that represent each state of the app (Tag 13 == Lesson 13, etc.).

Thank again for this amazing tutorial ;)