P7: IANA registry for schemes (issue 141)

Hi,

we introduced this in -12 (see 
<http://tools.ietf.org/wg/httpbis/trac/ticket/141>), however there's 
work left to do.

At least:

(1) Add "Considerations for new authentication schemes", and

(2) Something that registers the existing schemes.

For "Basic" and "Digest" I have prepared 
draft-ietf-httpbis-authscheme-registrations 
(<http://trac.tools.ietf.org/wg/httpbis/trac/export/1078/draft-ietf-httpbis-authscheme-registrations/latest/draft-ietf-httpbis-authscheme-registrations.html>). 
This hasn't been submitted yet, because it depends on the -12 drafts, 
and the submission window for -00 had already closed.

We can do this starting tomorrow; are we OK with this becoming -00, and 
add more details and potentially more schemes later on?

Best regards, Julian