Update with approved content to address issue 145

[maryjom]

See Issue #145

• Incorporate proposal 3C in IRC above into the general guidance for the 5 SC that pertain to “sets of documents/software programs” with the editorial change.
• Incorporate the updated Proposal 3 (above in IRC), into the Guidance in this Document section.
• Update the SC Problematic for closed functionality section using Proposal 4 with edits noted for consistency.

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