Timed Graph

The graph is now properly labeled for time and you can set various intervals that can be chosen through a right-click menu.
![screen1](https://cloud.githubusercontent.com/assets/7190144/4101886/3db1e208-310a-11e4-9ddd-0e2e5cfece76.png)
![screen2](https://cloud.githubusercontent.com/assets/7190144/4101887/3db95ede-310a-11e4-862c-e2eb004e284c.png)
![screen3](https://cloud.githubusercontent.com/assets/7190144/4101888/3dba00a0-310a-11e4-8d10-9bb58d9e0a8b.png)