deploy previewable page on pull requests

[capsulecorplab]

Is your feature request related to a problem? Please describe.
Currently, the options for previewing a pull request entails either using GitHub's asciidoc rendering engine to view previews on the GitHub UI or having to clone the repo locally and run a local build/server.

Describe the solution you'd like
Netlify provides CI services for custom builds. I think it's worth investigating how to set one up per pull request.

Describe alternatives you've considered
No alternative automated workflow strategies have been considered, as far as I know.

Additional context
https://www.netlify.com/blog/2016/07/20/introducing-deploy-previews-in-netlify/