Add summary stats for CLI

It is useful to have summary statistics for code coverage on the CLI as well as through a web browser

![screenshot 2014-07-28 09 39 46](https://cloud.githubusercontent.com/assets/205245/3718186/f636c19c-1632-11e4-8b8e-f161890e6945.png)

Global functions are verboten. Could be defined as a closure though.