[Feature][Wanted] Control over Streamquality

[ebosseck]

Add (URL-)parameters for selecting maximum Stream quality- 'Ideally it is possible to select a custom resolution / bitrate / codec for Video and audio. These parameters should be fulfilled best-effort. This means that it is possible that the final stream has a lower quality than specified, if the bandwidth is not up to the specified quality parameters, but it should use as much bandwidth as possible for the given p2p connection.