Updates for SD-CWT

[OR13]

This PR does a lot.

• Editors rework
• CDDL and EDN
• Updated IANA registration requests
• Add implementation report
• Revised diagrams
• Revised definitions

[OR13]

I spoke to @rohanmahy and we agree to merge early and often, and keep filing issues.

I'm hopeful we can publish an update to the data tracker before IETF 120 cut off.