Start playing at a specific time via url fragments

This uses URL fragments similar to youtube and as described in the video 
examples here:

http://en.wikipedia.org/wiki/Fragment_identifier#Examples
I am afraid that `es.upv.paella` is a hardcoded, magical namespace used throughout the app and wasn't too worried about attribution given that we're using source control.

Maybe plugins can live in another namespace, but I'm really not sure about that.