New: Collapsible sections

[elevatebart]

closes #1436

• Make sections collapsible if you ask for it
  • tests
  • Document new option collapseSections
• Adjust types in schema/config.ts (very minor) for sections
• Add comments on unclear global types and simplify them

[codecov]

Codecov Report

Merging #1487 into master will increase coverage by 0.07%.
The diff coverage is 100%.

Impacted Files	Coverage Δ
src/client/utils/renderStyleguide.tsx	75% <ø> (ø)	⬆️
src/loaders/styleguide-loader.ts	95.23% <ø> (ø)	⬆️
src/client/rsg-components/Context/Context.ts	100% <ø> (ø)	⬆️
src/client/rsg-components/Link/LinkRenderer.tsx	100% <ø> (ø)	⬆️
...rc/client/rsg-components/StyleGuide/StyleGuide.tsx	75% <100%> (ø)	⬆️
...rsg-components/TableOfContents/TableOfContents.tsx	97.72% <100%> (+0.85%)	⬆️
src/client/utils/getRouteData.ts	97.82% <100%> (ø)	⬆️
src/client/utils/filterSectionsByName.ts	100% <100%> (ø)	⬆️
...t/rsg-components/ComponentsList/ComponentsList.tsx	100% <100%> (ø)	⬆️
...mponents/ComponentsList/ComponentsListRenderer.tsx	100% <100%> (ø)	⬆️
... and 4 more

[sapegin]

Thanks for the pull request!

[elevatebart]

Hello @sapegin, do you think this Pull Request could be merged in?

[sapegin]

Sorry for slow review! Couple of minor suggestions ;-)

[elevatebart]

I took into account all of your comments.
@sapegin you have my green light to merge

[styleguidist-bot]

🎉 This PR is included in version 10.4.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀