CR exit criteria

As requested, I've tried to put into writing what I was suggesting on 
today's call.

This is a fairly tough set of exit criteria, going a ways beyond what 
W3C process requires.

    https://www.w3.org/wiki/Socialwg/AS2_CR#Exit_Criteria

    currently:
    https://www.w3.org/wiki/index.php?title=Socialwg/AS2_CR&oldid=87448

I lean toward this kind of higher bar perhaps because I've seen a few 
too many specs become a Recommendation and never actually be widely 
implemented.   That may just be my bias, though, and I wont object to a 
lower bar.

      -- Sandro