Change 'Show' and 'Back' links into explicit 'Curation dashboard' and 'Cancel' links.

Closes #115

![screen shot 2014-02-10 at 4 00 18 pm](https://f.cloud.github.com/assets/96776/2133245/0b48e6ec-92c0-11e3-810d-dd5f592eb9c4.png)