Refactor manual views and preview code

As part of the ongoing development, I've redesigned the #index and #show pages to better match the designs. Some workflows have changed, but this is pretty close and will continue to be worked on. In this PR is also a fix for preview not working on new specialist documents that I found along with refactoring the preview JS to allow for the button and the container to be positioned in different places.

Screenshots below:

# #show

![screen shot 2014-05-15 at 17 11 54](https://cloud.githubusercontent.com/assets/449004/2987241/24472ac0-dc4c-11e3-8341-446eaab0315f.png)

# #index

![screen shot 2014-05-15 at 17 13 11](https://cloud.githubusercontent.com/assets/449004/2987247/2b06e6b6-dc4c-11e3-9c09-035f945675d0.png)