Amazon - CSS now applies properly, stars also generated properly

/cc @yegg @russellholt 

This is a quick fix for the display of single items. Currently they're being handled in a funny way because this was written before `Spice.render()` had a nice way of handling single items.

Amazon.js should really be updated appropriately. I can push those changes here unless we want to release this as a hotfix?

Also, both the single_item and detail templates were wrapping everything in an extra `<div>` so I've fixed that.

![image](https://f.cloud.github.com/assets/873785/1432310/2a55a33a-40dc-11e3-93fe-07813a890a34.png)