Enhancement/218 line coverage for all files

solution for #218 / first version you can give a try

* all files without coverage report are set to 0 coverage
* use non comment lines of code for coverage calculation
* all lines of the files are marked red (also comments and preprocessor directives)
* source and header files included - with header files I'm not sure (but there could also be code inside)?

**Please try and give me feedback.**