Adds audio-js library.
Adds audio views and generic content model clientside code.
Adds first pass api endpoint for content resource.
Integrate audio content into topic sidebar.
Implements extra_fields attribute on content models.
Generalize extra_fields parsing.
Adds first pass content data parsing on server.
Adds first pass contentlog.
Monkey patches audio-js to properly find its dependent files.
Merge branch 'develop' into audio_js
Uses _.extend to parse extra_fields. Adds additional fields to contentlog.
Adds updated audiojs (from rtibbles/audiojs) that adds generic event triggers.
Updates audiojs. Adds contentlog instantiation to audio view.
Adds contentlog views and time_spent fields. Adds schemamigration.
Adds progress tracking to audio views.
Fixes #2401.
Fixes event handling for audiojs timeupdate events.
Adds defaults and default database_attrs to contentlog model.
Adds icon for audio items in sidebar.
Adds styling for audio player.
Adds points display and statusModel points updating.