Move all view stuff into the App view

View is a Backbone View.
Media becomes a Backbone Collection

And Medium its Model.
Load media and sections from the server, on creation of the App.
Sections as a Backbone Collection of Section

Everything stored in localstorage via Backbone.localstorage now.
Renamed from chapters to sections.
Extract communication with server in its own component
Push some of the behavior in Sections Collection