Create authenticate feature

[lem-onade]

No description provided.

[woutermont]

I'd like to see the events and actions more loosely coupled (cf. what I wrote you in Slack about the add test collection flow): events should indicate something that happened (e.g. CLICKED_LOGIN), while actions are something that should be done (e.g. setSessionInfo). Events should be as specific as possible, and actions as abstract as possible. That way, we don't write one action per event, but multiple events can be handled by one action; and also the other way around: multiple actions can handle the same event type depending on the state.

[wouteraj]

Already looks very good!! I'm also a big fan of the finite state machine diagram, definitely something we should keep doing.

[wouteraj]

Looks good!! I added some stricter type checks, and reworked some of @woutermont 's previous feedback. Look good to me (given that tests will be written in #35 ;-)).

[woutermont]

Very nice!

[wouteraj]

closes #50