Added feedback to test module and debug mode option to command line. Fixed bug in the way Z3/Test concurrency was handled. Small changes/fixes in readme. Added more comments.

Fixed bug(s) in evalBin
Equivalence class tests also use the QuickCheck module now.
Added a "run mode" to Main.hs (Debug / Release). In case of Debug, the results of QuickCheck and Z3 will be compared (and an error will be thrown if they have different results). In Release mode, this doesn’t happen.