Feature/anonymous user event page

I did some preperation here for voting/suggestions for lisa.
Development is: Eventlink will be displayed, anonymous users can access event pages via /voting/:id

what has been developed:
a.) when i go on    /voting/:id  i´ll  get logged in and redirected to the event (middleware: ensureNotAnonymous)
b.) proectetion of ressources from anonymous user, middleware: ensureNotAnonymous
c.) small labeling bug fixed at events (suggestion/preview enabled was displayed wrong)
d.) accesskey from event removed
e.) basic setup of voting (the page can be seen)
f.) hiding of the menu/player (... had to use ng-if ... not ng-show/hide ... subtle difference!)

Open:
I do not know how we get the user into the database yet.
Currently, it is hard coded in the passport.js and it is assumed that the user exists already in the database

Event link could be nicer

Protection of the ressources in the app (Manuel said he will do this)
Acutal Voting implementation => Lisa
put the configuration in a separate `config.js` file