IANA considerations needs to be updated

[sbingler]

Some aspects of the IANA considerations section are outdated and should be updated:

• The “Cookie” and “Set-Cookie” registrations from RFC 6265 have been moved from the “Permanent Message Header Field Names” registry to the “HTTP Field Name Registry”

  • Update Sections 9.1 (Cookie) and 9.2 (Set-Cookie)

• The word "Registry" should be omitted from registry names.

  • Update Section 9.3 (Cookie Attribute Registry)