Add integration with Sannes

You can start with setting the restaurant where you are buying from, e.g. resolve #43. Then if you select Sannes, when adding what to eat, auto completion from sannes.chalmers.it/data/pizza.json can be used.

Start by resolving issue #43 and tracing the restaurant-selection flow. Check how Sannes can use sannes.chalmers.it/data/pizza.json for food-name autocomplete; done means Sannes can be selected and its pizza data is available while adding an order.

Written by the indexing model from the issue text.