style(rxApp): Add styles and documentation for Account Info box

Closes #555.

See https://jira.rax.io/browse/EOD-2
Notes for myself, all bundled into one comment to reduce spam:

- the `return deferred.promise` block becomes

```js
return protractor.promise.fulfilled('');
```

- Use of `by.binding('title')` over `$('.info-title')`

- in demo, create a title-less info box

- in demo, put an rxNotify stack inside of info box, trigger it

- in `exports`, expose a `main` property that grabs the (likely) only instance of the directive on the page