Major code review, cleaning the code and adding a lot of comments. Also
implements a separate store to keep entities with a reference count and
garbage collection. This closes#15.
Known issues at the moment are:
* Webplayer is no longer working, it has to be refactored.
* AlbumPage is to be implemented.
Now able to play a single file, in a format supported by your browser.
* Playlists not yet supported.
* Volume is a simple on/off switch.
* Repeat / Random not yet supported.
* Keep track of pagination in the store
* Use Immutable in reducers
* Finish i18n, every available strings are now translated in English and French
* Add a loading indicator
* Premises of API error handling
* Better locale negotiation
