Improve initial inapp page (bug 1059959)

- Hide table until user clicks 'Add a product'
- Add documentation link

![screenshot 2014-09-04 15 48 13](https://cloud.githubusercontent.com/assets/119884/4155642/7891572c-346c-11e4-84aa-93a5f443912b.png)
![screenshot 2014-09-04 15 48 22](https://cloud.githubusercontent.com/assets/119884/4155644/7e18a128-346c-11e4-866f-808d4f3ca5d7.png)


There shouldn't be a space before the `{% if %}` so the class names are formatted correctly when you look at the output. The space should only be added when the class is added:

```
class="devhub-form island{% if not products %} empty{% endif %}"
```