Bring in new menu, changing build step

[njbotkin]

I mostly want to know what you think about the rollup changes. I should have made a PR with just them separately. Bah.

[TehShrike]

maybe there should just be a public/*.css rule?

[TehShrike]

I'd strongly recommend using data attributes instead of dynamic classes to represent state:

<div data-visible="{{visible}}" class="slide-out">

Then you can use the selectors [data-visible=true] and [data-visible=false].

[TehShrike]

Looks legit to me. One possible change I see: since process() returns a thenable, you can resolve it directly with Promise.resolve instead of constructing your own Promise.

The main advantage there is that all errors/responses are represented in the new Promise, whereas right now this promise is only getting resolved if execution makes it all the way down to line 40 without any errors happening.

style({ content }) {
	return Promise.resolve(postcss([
		require(`precss`)({
			import: {
				path: [ `client/global-css` ],
				prefix: ``,
			},
		}),
		require(`autoprefixer`),
	])
		.process(content)
		.then(result => {
			return { code: result }
		}))
},