Add stopwatch support

This PR needs egeloen/ivory-http-adapter#42 and basically, all is in the title and the screenshots :kiss:

![screenshot from 2014-11-11 20 10 22](https://cloud.githubusercontent.com/assets/737992/5000758/1bed9478-69ef-11e4-86b1-36c1fe469848.png)
![screenshot from 2014-11-11 20 12 20](https://cloud.githubusercontent.com/assets/737992/5000761/21ae9d12-69ef-11e4-8de4-adac984de0a2.png)
![screenshot from 2014-11-11 20 12 51](https://cloud.githubusercontent.com/assets/737992/5000766/2c38bde4-69ef-11e4-81de-84acfc3d1b36.png)