client: add mtgTracker.auth
client(mtgTracker): redirect to login on 401 error
client: add home
client(mtgTracker.collections): use iife for module definition
client(mtgTracker): remove httpInterceptor config
api: fix response on OPTIONS request
api: do not crash on empty payload
api(CollectionsController): request authentication
api(Sinatra/Authentication): allow OPTIONS response