Optional mp3 fields

Album, label, year optional when adding mp3, nicer sync template

jQuery bugfix

Fixed include of jQuery and jQuery-UI

Track sync bugfix

New stuff:

• Track sync now plaintext
• Fixed number year in track search
• Show artist origin in printout
• Various bugfixes
• About page with license link

Website sync

Brief list of new stuff:

• synchronise saved tracklist to RŠ website
• fancy buttons for copying to clipboard and printing out
• see labels when browsing search results
• see genre / origin of music in a tooltip
• new favicon!
• bugfixes and minor style improvements
• relicense to AGPLv3 or later

Past list of functionality (wasn't bothered to create tags):

• mp3 track support
• album editor
• sorting improvements