Move sidebar toggle icon to the left.

<img width="1434" alt="screen shot 2016-12-28 at 4 14 10 am" src="https://cloud.githubusercontent.com/assets/346288/21521689/271662a6-ccb4-11e6-8534-b40a1eb8e1d9.png">


Some potential ideas:

1. http://takien.github.io/jPushMenu/
2. http://callmenick.com/_development/slide-push-menus/