collection and shelf detail previews (bug 1035445)

![](http://f.cl.ly/items/1s3S0W3V1G382k3X1M2H/Image%202014-07-17%20at%204.13.36%20PM.png)
For the record there's nothing about this that I like or agree with.
It shows we modify ```.mkt-tile```, why do we need that?