initial tracking infrastructure
Merge branch 'master' into tracking
add GUM tracking
Merge branch 'master' into tracking

Conflicts:
	index.html
Merge branch 'master' into tracking

Conflicts:
	index.html
Fixes simulcast layers ordering.
Merge pull request #128 from jitsi/tracking

Tracking
work around https://code.google.com/p/webrtc/issues/detail?id=3807
add missing tracking.js to #128