Small style tweak

I've tweaked the list styles for (IMO) better alignment of unordered lists. It centres the padding around the list bullets for a more consistent look.

Full Width
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Existing:
![existing](http://f.cl.ly/items/3L0z280N0R2F3o0Q1t3f/Screen%20Shot%202013-09-03%20at%207.28.25%20PM.png)
New:
![new](http://f.cl.ly/items/3Y3f1P2x3S3s0a3N3M1N/Screen%20Shot%202013-09-03%20at%207.28.09%20PM.png)

Mobile Width
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Existing:
![existing](http://f.cl.ly/items/21072R2Y2M0F1c1C3l1N/Screen%20Shot%202013-09-03%20at%207.30.38%20PM.png)
New:
![new](http://f.cl.ly/items/0x2o1A3M002h310K2c3M/Screen%20Shot%202013-09-03%20at%207.30.23%20PM.png)