E2e rx age

Closes https://github.com/rackerlabs/encore-ui/issues/319
I see what happened...I must've been running a different setup in my repl:

```js
> re = /^(\d+)(\s+)?([a-z]+)$/
> '10d'.match(re)
["10d", "10", undefined, "d"]
```

I'll update this to `match`, because that's what I was actually thinking when I wrote this.