Remove pubsub functionality

Pubsub uses the global Backbone object. When multiple FS instances are
used with the same Backbone object, they listen to eachothers pubsub
messages. To avoid this, we could bake Backbone into FS or remove all
pubsub and only trigger events from FS' main view. We choose the latter
to avoid overhead. This means we got rid
of the (hilib) baseView, baseCollection and baseModel, because they all
implemented pubsub. This also means we have to listen to the FS for the
'unauthorised' event, it is no longer triggered directly on the Backbone
object.