#622 Make command bar buttons responsive

@mdeiters noticed that the buttons are rather stuck together when you have a small window:

![Buttons not being responsive](https://d8izdk6bl4gbi.cloudfront.net/frame_0/https://d8izdk6bl4gbi.cloudfront.net/frame_0/https://d1015h9unskp4y.cloudfront.net/attachments/a8813f3e-8c59-4221-a83d-3217406841cd/Screen%20Shot%202014-05-29%20at%203.16.33%20PM.png)

So now they have some space between them!