[sipcore] Updated 4244bis and new call flow document

[Mary Barnes <[e-mail]>]

Hi folks,

The 4244bis draft has been updated and a separate call flow document
created per the earlier summary of proposed changes:
http://www.ietf.org/mail-archive/web/sipcore/current/msg02647.html

http://www.ietf.org/id/draft-ietf-sipcore-rfc4244bis-01.txt
http://www.ietf.org/id/draft-barnes-sipcore-rfc4244bis-callflows-00.txt

There are  two voicemail examples in the new call flow document.  The
4244bis has 3 call flows - the basic sequential forking and two
privacy examples. All the rest are now in the call flow document.

The other changes we made were updates to the UAC, UAS and application
considerations section - adding additional text as to how the UAC and
UAS process hi-entries (including related to responses).  The
application considerations section now describes how the tags can be
used to derive specific information and the past guidelines were
removed since 4244bis has much definitive guidance on the normative
aspects of the header (i.e., SHOULDs replaced with MUSTs, privacy via
anonymization rather than removing entries, etc.) as summarized in
Section 11.

Please review and provide any additional comments. We believe that
4244bis is pretty much ready to go. We can fine tune the details in
the call flows and should be able to get that ready very soon, as
well.  Let us know if you see additional use cases you would like to
add.

Thanks,
Mary et al