#492 TV support wishes

[Rion]

1) display current channel in window title
2) unmodal tv editor dialog
3) switch channels right from tv editor
4) scan for new channels (update current list)
5) display tv button on toolbar when tv tuneris available
6) make audio volume working (at least on linux)
7) switch channels by scroll (maybe with modifiers)

Tested system: ubuntu 11.10