Split view on dashboard

Dashboard has been split into two vertically with list of assignments on the left and the assignment stats on the right. Currently having issue between controller and view where it is sending a nil reference when the link is clicked.

![image](https://cloud.githubusercontent.com/assets/6497466/4821847/f617d768-5f35-11e4-95d9-d9094e943ca2.png)

That's true, although I don't think that's a high priority right now. I doubt many admins will be using MarkUs on smaller screens.