Improve initial inapp page (bug 1059959)

- Hide table until user clicks 'Add a product'
- Add documentation link

![screenshot 2014-09-04 16 35 54](https://cloud.githubusercontent.com/assets/119884/4156324/1ddae378-3473-11e4-84ac-2530ceac8d4f.png)
![screenshot 2014-09-04 16 36 01](https://cloud.githubusercontent.com/assets/119884/4156325/213d0cc6-3473-11e4-8160-f50398881dfb.png)