Code coverage2

Hi, 

this pull request contains the Code-Coverage Feature for the unittest runner written by @yarbu, via the Branch of @OutOfBound

The pull contains an additional bugfix in coverage.xsl, because the file- and folder-nodes could not be found by jQuery under Chromium 18 on linux and Firefox 14 on windows. 

We tested this feature yesterday, it works as expected. Memory is no problem after all if you want to run only your application unittests. 

Example to start the unittest with enabled code-coverage: 
``` bash
unittest -c `pwd`/src/main/php src/test/resources/unittest.ini
```