Layout changes for non-image collection previews

Closes #613 
Closes #340 

> Layout changes to:
> - [x] get rid of the table layout, 
> - [x] use icon font instead of image, 
> - [x] drop the "1-3 of" text from the label,
> - [x] use the standard "online" bg color (#009b76) for the label,
> - [x] make the label the same size and font as the At the library etc. labels
> - [x] add margin below the other expand-o sections.

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![image](https://cloud.githubusercontent.com/assets/302258/3900974/80bd462e-229a-11e4-8fe3-c390d11e359d.png)
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![image](https://cloud.githubusercontent.com/assets/302258/3900975/89243d0e-229a-11e4-80a4-506359c68f59.png)

@jkeck Removed `format_key` method from `concerns/collection_member.rb`, and updated this PR