"Custom" column should not appear negative

*Adding neutral class.
*Custom column is now "neutral" with a minus icon instead of red with an 'x'

**Example:**
![neutral](http://content.screencast.com/users/max.peterson/folders/Jing/media/af567f77-73fe-4fe4-aec4-abe961e13dab/00001057.png)

fixes #25