line-height for constraints

When contraints wrap to two lines, they needed more space. 

![constraints-vertical-collision](https://f.cloud.github.com/assets/149304/1860849/9cc4eb92-77b9-11e3-8127-84144a7531e1.png)

Fixed by increasing line-height of the .constraints-container, then had to adjust padding on other elements to leave spacing the same. 

![vertical-collision-fixed](https://f.cloud.github.com/assets/149304/1860854/a34be5e2-77b9-11e3-9ab9-bdf9c33b594f.png)

(I'm also trying to figure out a solution to when the screen is so narrow and one individual constraint so lengthy that it goes off screen, but that's proving very tricky, so will do it as a separate PR, if at all)