[RFR] Add temperature dynamic graph

- [x] Create line graph class
- [x] Add colored area under value line
- [x] Add smoother animation
- [x] Stabilize temperature measures

Current state:
![prizes](https://cloud.githubusercontent.com/assets/688373/3725856/655d2340-168d-11e4-85f2-19a0d51ee6cd.gif)