Revert "Revert 5461821..41fd52b"

This reverts commit 20da7282533e57a3c8778811324a02cb7690cb7a.
Merge remote-tracking branch 'upstream/master'
Use constraints to avoid CN. Tweak error msgs.

Use CreateOffer/Answer constraints to ensure that the SDP doesn't contain CN; remove obsolete code to do this manually.
Fix adapter.js symlink
Ignore PYC files
Add apprtc-juberti as distinct from googlechrome/apprtc
Merge branch 'master' of https://github.com/juberti/webrtc
Fix bug in mergeConstraints

This caused VoiceActivityDetection to get dropped.
Revert "Revert "Revert 5461821..41fd52b""

This reverts commit faa8fa770844a63444531e300d02c4139861d3df.
Revert "Add apprtc-juberti as distinct from googlechrome/apprtc"

This reverts commit 9d7291d8d8ca09ca8b376312cea72b7975bb96c0.
Merge pull request #8 from juberti/apprtc1

Fix how CN is stripped in AppRTC.