feat: Pug-to-Handlebars Pipeline

[wyrmisis]

Intent

This changeset adds Pug to our workflow.

Pug is a less verbose templating engine that outputs to HTML-like syntax. Thankfully, for our purposes, it'll convert to Handlebars just fine.

Why the heck?

• HTML is super verbose. It's easy to get lost in a tangle of tags.
• Handlebars templates aren't pre-compiled; they handle the inclusion of partials at runtime. Oftentimes, partials are used for code-sharing and code-splitting. Why foist that cost onto users?

[wyrmisis]

With a new system in place, I think it might be beneficial to make a note of pug and a link to their documentation somewhere in CONTRIBUTING.md so the on-boarding process for new people is as smooth as possible.

Other than that, I like the look and functionality of pug from what I can see.

Absolutely correct. I'm rolling through existing templates to convert them to use Pug right now, but I'll be sure to update our documentation to mention it.

[anthonyronda]

I'll look at this after the bugfix release :)