Show track on talk list

[stefanor]

15:43 < gwolf> tumbleweed / terceiro: Suggestion / feature request for Wafer — in the listing 
               of submitted talks for Content Team's review (/talks), could you add a column 
               with the talk's track?
15:44 < gwolf> Not that it's fundamental, but it can be a nice addition
15:44 < gwolf> (of course, extra points for being able to sort by different columns ;-) )

This would mean:

1. Including the track on the UsersTalks view.
2. Adding a sorting query string parameter.