Add an interface to foodsaving.world

[lentschi]

I'm in contact with the developers at https://yunity.org who are working on extending the current API to allow adding food baskets for web apps such as foodsharing.*. As soon as that is done, I will consider providing a function, that allows ticking product entries and then create food baskets over a designated menu point.

Depending on the final foodsaving.world API, this will quite likely require issue #2 of the wrapper repository to be completed first.