Simple example of documentation-driven development

1. Install the dependencies:

   $ pipenv install

   $ npm install dredd

2. Activate the environment:

   $ pipenv shell

3. Run the app:

   $ FLASK_APP=app:app flask run

   Visit the auto-generated documentation at 127.0.0.1:5000/docs

4. Run the Dredd tests:

   $ ./node_modules/.bin/dredd oas.yaml http://127.0.0.1:5000 --hookfiles=./hooks.py --language=python --server "flask run"