Move share buttons

This moves the share buttons from the right to the left of the page. The width of the lefthand column has meant some re-styling which is applied at the bottoms as well for consistency. 

Before: 

![bottom-befor](https://cloud.githubusercontent.com/assets/986155/2722011/4b3e7b5a-c582-11e3-8755-fc40d335c712.png)
![before-top](https://cloud.githubusercontent.com/assets/986155/2722014/51eb9384-c582-11e3-94d4-bd90af154c80.png)

After: 

![left-share-buttons](https://cloud.githubusercontent.com/assets/986155/2722056/fcb68fda-c582-11e3-9229-b91ade78a055.png)
![bottom-buttons](https://cloud.githubusercontent.com/assets/986155/2722057/fcb6cd38-c582-11e3-8ac5-2a03011b1c93.png)