Source files of the Gridline Development design system as published online.
  tokens.json    every brand token with its usage note (the design system's own format;
                 for code, use 05-App-Kit/tokens.css or tokens.json instead)
  README.md      the brand book as text
  components/    the preview cards: each folder has a preview.html and a README.md
  assets/        notes for the logo and imagery groups
The preview.html files expect the design system page to supply tokens and fonts, so they are
reference code, not standalone pages.
