Fixes freezes in Pa_ReadStream, Pa_StopStream and Pa_WriteStream and incorrect causes of paInvalidChannelCount errors in PortAudio on Windows/WMME. Mitigates an issue with hightened CPU usage (on all supported operating systems) related to hotplug.

Commits work in progress on refactorying the call-related user interface for the purposes of audio and video telephony conferencing over single or multiple protocols and Jitsi VideoBridge.

Implements a mechanism that allows JMF Controls registered in the  codec implementations to be accessed in MediaStream. Adds a FECDecoderControl interface and uses it to collect FEC statistics in MediaStreamStatsImpl. Adds a "Packets decoded with FEC" line in the call info window.

Fixes issues with video conferencing such as a failure of the local video to be displayed and a limitation of the conference focus with respect to requiring it to capture video as well.