New version of editor's draft (20130116)

Hi

A new version of the editor's draft is available.

Dated version: 
http://dev.w3.org/2011/webrtc/editor/archives/20130116/webrtc.html
Living document: http://dev.w3.org/2011/webrtc/editor/webrtc.html

Changes include:
* Changed AudioMediaStreamTrack to RTCDTMFSender and gave it its own 
section. Updated text to reflect most recent agreements. Also added 
examples section.
* Replaced the localStreams and remoteStreams attributes with functions 
returning sequences of MediaStream objects.
* Added spec text for attributes and methods adopted from the WebSocket 
interface.
* Changed the state ENUMs and transition diagrams.
* Aligned the data channel processing model a bit more with WebSockets 
(mainly closing the underlying transport).

Please review and provide feedback.

Adam (for the editors)