readme & docs need some work

[sircfenner]

• [ ] Provide a short readme in addition to the docs link
• [ ] Revisit installation instructions in docs
• [ ] Revisit usage page (e.g. correct vendor/packages terminology)
• [ ] Mention that theming can be overriden as and when needed
• [ ] Add to list of projects using this library (e.g. Archimedes 2, Inserter)
• [ ] Revisit page color theme (e.g. text doesn't have great contrast against background)
• [ ] Placeholder pages for missing components