Drawer Component

[dwhitney]

Hey, I like the looks of this library (as I like the looks of everything your team has built!), but the one component missing that I need is a Drawer component, like this one from Material UI. I'm happy to make a PR if this is something you'd all be interested in.

[maddie927]

It'd most likely be something we'd use eventually if you do make a PR. The lumi-components documentation site (in this repo, docs/App.jsx) implements a really basic one which could be replaced to start.