Updated ICE RFC reference

Ignore-this: 3184e284ac64f996df2ed804d4d567df

darcs-hash:20140905152504-56b4d-a464bb78366e843c7ad9d4dab59f1b905417d19d
Report stream failure in MediaStreamDidEnd

Ignore-this: dca91d6c3e687c10a4407452e9fb86ff

If a stream fails (that is, MediaStreamDidFail was posted) remember the failure reason and pass it
as notification data. It will be None in case there was no error.

Also, get rid of the Failure objects attached to MediaStreamDidFail notificacions on MSRP streams
since they were never found useful.

darcs-hash:20140905153227-56b4d-6989c9077f21750249f2092cda1677b6f51344e5
Avoid failures on VideoTransport.send_keyframe

Ignore-this: 9403f0d8c41c4e42082188d0bab92bba

darcs-hash:20140908104016-56b4d-587e38660f8b2769fbf397f87b52d46b602eeeb3