Manual of Style & pubRules fixes

[AlexDawsonUK]

This PR applies some editorial fixes in-line with the W3C Manual of Style:

W3C Manual of Style preferred terms:

• style sheet over stylesheet (it has a space in CSS)
• white space over whitespace
• variables to factors (variables conflicts with CSS)
• The W3C to W3C (Sans is preferred).
• they/them over he/she/him/her (etc).
• Added some more abbreviations.
• Removes "normative" mentions as per (glance.html: editorial: replace "normative" tech spec w "full document" #120).

I've also applied hotfixes where prior bugs have occured and drawn all the docs in-line with pubRules:

• All div/sections now have an associated ID.
• QuickRef header now links to the PDF alternative.
• All documents now have a required SoTD template.
• Increased luminosity of click regions (WCAG friendly).
• Added dark mode to all documents via ReSpec.

I've applied a couple of editorial tweaks to two SC's based on discussion with Rose to align with W3C QA spec.
I also fixed some improper use of double spacing, case usage, and non-standard characters.

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[TzviyaSiegman]

this isn't a final version, so don't think we need to include the statement that changes cannot be addressed in this version (yet)