Add description of how to test with W3C tests.
Add description of how to test with W3C tests.

Zauberstuhl/adapter,Zauberstuhl/adapter,shines/adapter,calebboyd/adapter,jan-ivar/adapter,webrtc/adapter,shines/adapter,Acidburn0zzz/adapter,xdumaine/adapter,Acidburn0zzz/adapter,4lejandrito/adapter,harme199497/adapter,shines/adapter,harme199497/adapter,xdumaine/adapter,jan-ivar/adapter,calebboyd/adapter,webrtc/adapter,calebboyd/adapter,harme199497/adapter,Acidburn0zzz/adapter,4lejandrito/adapter,4lejandrito/adapter,Zauberstuhl/adapter