Documentation for the Validator.nu full-stack test harness

I documented the full-stack test harness of Validator.nu:
http://wiki.whatwg.org/wiki/Validator.nu_Full-Stack_Tests

The implementation itself has existed for a while, but I hadn't gotten  
around to documenting it. There aren't actual test cases to speak of,  
yet, because HTML5 has been too unstable.

The test harness implements what was discussed on this topic at TPAC  
2007.

-- 
Henri Sivonen
hsivonen@iki.fi
http://hsivonen.iki.fi/