Research and choose API docs engine

[linc]

Current candidate is Slate: https://github.com/lord/slate

[hgtonight]

Ruby?!?! 😭

[linc]

The big thing is the end product, especially the tri-column layout of nav > text > examples. We'd also prefer if it accepted Swagger JSON to build, and any other automation that's possible. We've barely looked at it so far. We're pretty agnostic about what these third-party systems run; the new docs engine is Go-based. ¯_(ツ)_/¯

[tburry]

Currently we are using swagger UI and won't be changing in the near to medium term.