TODO

api:
  multi-user jingle stuff

backend:
  pausing/holding
  support playing file from bytearray
  support recording
  use pulsesrc/sink and AEC mode, no need for speexdsp on linux
  consider adding windows/mac AEC support into device elements
  switch to using official gst appsrc/sink
  use farsight

gstreamer:
  0.11: fix udpsink (#534243)
  0.11: merge directsound (#584980)
  0.11: ensure osxaudiosrc/sink stuff is merged (#602121)
  0.11: ensure osxvideosrc stuff is merged
  theoraenc screws up when looped (#562163, unresolved)
  cleanup speexdsp/speexechoprobe and merge to gst
  get all elements we depend on from gst-plugins-bad to graduate to -good
  figure out windows video capture situation. is ksvideosrc the full answer?
  ksvideosrc device enumeration
  v4l2src that supports only image/jpeg fails if independently set to READY
    before changing to PAUSED.  see devices.cpp