Hours per week label

I added an "hours per week label" to the schedule page UI. I figured this would give students an easier and more accurate method of counting up their weekly hours rather than doing it manually. 

Here is a screenshot of the changes I made to the UI:
![newui](https://cloud.githubusercontent.com/assets/6456601/4179941/768239c4-36dd-11e4-9b65-c5f656a19971.png)

I propose a different algorithm: 
Each course will be rounded to the nearest 30 minutes and then added together for the final count. This will account of all lengths of time and is more intuitive for the user, since we all count class hours as multiples of 30 minutes.