[reSIProcate] latest webrtc update - JsSIP now registers

[Daniel Pocock]

I've now made more fixes on b-webrtc

One critical improvement is that JsSIP now registers with repro, and
I've been able to make calls between two JsSIP users

Calling between JsSIP and SIPml5 hasn't worked though

I've also updated the list of known issues in the wiki page, and added
some comments about NAT traversal:

http://www.resiprocate.org/WebRTC_and_SIP_Over_WebSockets