[Sls-mhdc] Updated Green Book for CCSDS-123.0-B-2

[Kiely, Aaron B (US 332B)]

Dear Working Group,

I have uploaded an updated draft of the Green Book for 123.0-B-2 to:
	CWE Private / 123.1-B / GreenBook / 120x2g2-2020.05.18.docx

In this draft I have accepted all previous edits, including a new section 5.8 (misregistration) contributed by Mikhal (thanks!), and made some suggested edits to this new section.

Regards,
Aaron