Support for `>` selector

Given this template:

```
    <address>
      <figure
        class="avatar"
        style="background-image: url('http://lorempixel.com/400/400/business');"
      ></figure>
      <a>@somebody<a/>
    </address>
```

This selector doesn't work as expected:

```
address > figure {
    width:== 100;
    height:== ::[width];
}
```

However, it works fine without the `>`
