Binding of metadata to html objects.

Bind the value of a button to the playing artist, by attribute; playing album by property; playing composer by property. Skip tracks to see the data change. The composer should currently (4/2/7) fail as it is not a key supported for access by the songbird object.


- this should have artist
- this should have album
- this should have the track title
- this should fail (composer)
- this should fail (foobar)