Add a simple sir-trevor widget to include an image and title for a document.

This widget currently will just take a known ID of a document in the local
index and display the configured title and image thumbnail.

There is a checkbox to configure weather to show the title or not in
case the user just wants the image for a document that has a title.

Fixes #33 

![screen shot 2014-01-29 at 3 32 31 pm](https://f.cloud.github.com/assets/96776/2035753/b100978c-893e-11e3-8319-55273741065b.png)

![screen shot 2014-01-29 at 3 32 23 pm](https://f.cloud.github.com/assets/96776/2035754/b51df5c6-893e-11e3-9cdb-5d54c9ce934b.png)