[IETF-PKIX] Revised OCSP Draft

[mmyers@xxxxxxxxxxxx]

I've revised the OCSP draft on the basis of recent comments and debate.
Notice of its availability in all the usual places should be showing up in
due course.  The revisions include:

- specification of HTTP 1.1 vs. 1.0
- elimination of the prior_to field in the request
- addition of a {produce_at, expires_on} interval in the response
- addition of requirements on the periodicity of pre-production of responses

With the exception of the first one (which has to do with 1.0 being an
Informational document while 1.1 is Standards Track), the changes address
the replay issue and scalability factors.

I left the abstraction of the trust model as it stands, although there's
some need for refinement to further reduce complexity in the non-CA trust
model.