How to add a new cookbook

1. Create a new markdown file inside www/docs/cookbooks with the content you want;
2. Add it to www/mkdocs.yml, under the Cookbooks section;
3. Open a pull request with these changes;
   1. Please use the following commit message template: docs: how to X
4. You're done! Thanks for the contribution!

You can also test your changes locally by running task docs:serve and browsing http://localhost:8000.