Improve component discoverability on website by switching to single-page docs

[jilliankeenan]

Problem
The current search/filter bar in puppet.style only filters by component name. The issue here is discoverability when a developer might be searching for a "dropdown" when the design system names it a "select" for example.

Solution
Go back to a single-page scrolling Storybook implementation instead of breaking each component out into a separate page so the developer can ctrl-f to do a full-text search. Single-page is the Styleguidist default so we should be able to just switch that config setting back.

Do a pass on the docs and make sure common synonyms for component appear in the text, e.g. make sure the word "dropdown" is included in each of the three *Select components.