Add UPnP compatibility about scream HOT 1 OPEN

Thanks for the offer of donations, but I see little chance of this working.

• I already implented RTP support in a (outdated) branch. It did work, but there's added CPU burn due to the byte reordering. Also, RTP receiver can't handle the fact that Scream will stop the stream when there is no audio playing. Implementing silence transfer in Scream is complicated, because it is not driven by its own timer loop, but the data pump from the Windows Sound Subsystem.
• UPnP is more than just media formats, it defines rendezvous mechanisms for sources and renderers. In the kernel, this would be hard to implement. A userspace daemon could do that, and then send the Unicast target to the kernel driver. Still, I'm not inclined to code that. And even if I would, we still would need to support some standard media format, which would have to be PCM, since you would not want to do codec transforms inside kernel space, without hardware helpers.

from scream.