charts for gauge- and counter-metrics

* added charts for gauge- and counter-metrics (with tooltips)
* changed colors for environment and properties subheaders

![screenshotmetrics](https://cloud.githubusercontent.com/assets/8779225/4393229/e557d35a-4415-11e4-9910-62cf434018f6.png)
![screenshotprops](https://cloud.githubusercontent.com/assets/8779225/4393236/f1b6cb10-4415-11e4-8020-cff521cce931.png)