[Sls-mhdc] White Book for CCSDS-123.1-B updated

[Kiely, Aaron B (332B)]

Dear Working Group,

I have uploaded to the CWE an updated draft White Book:
	CWE Private / 123.1-B / WhiteBook / 123x1w1-2017.09.28.{pdf, doc}

Changes include:
- 2, 3.1, 4.1, 5.1: revised/updated these non-normative sections
- 2.2: added this new section to comment on backwards compatibility
- 3.5: generalized supplementary information tables to include also 2D supplementary tables
- 4.4: updated to reflect anticipated resolution of “fast” mode for neighbor- and column-oriented local sums. (“Fast” and “legacy” now called “narrow” and “wide”).
- 5.3: minor changes in terminology used for header elements, some streamlining of text
- 5.4: revised, primarily to better describe how encoding of periodic fidelity information gets mixed in with encoding of mapped quantizer indices, fixed a mistake in description of BI encoding order in 5.4.2.2
- Annex A: ICS now written.

Regards,
Aaron