Add file browser + other updates.

* Updated JQuery to v1.9.1.
* Fixed minor incompatibilities with new JQuery.
* Added file browser.
* Added setting for default file browser starting location.
* Separated extra controls into their own box.
* Separated playlist update function from status update function.
* Playlist and status update immediately when a new playlist item is
selected from playlist, or added from file browser.
* Lots of minor code rearrangement.
Added button to open filebrowser in new tab.