New Features

I've added a number of new features:
* Changed the echonest search to using the Spotify API
* Added Shuffle indicator and button (may want to replace the button in the sprites.png file as I didn't have the original background and made my own one with rudimentary photoshop skills)
* Added current playtime indicator
* Fixed duplication in the Spotify API requests so we should only have one of each.
* Fixed bug with dropping track/playlist not refreshing the currently playing track