Added unit testing
Improved unit testing and added all examples starting with "test" in the .cub files
Removed trace in favour of traceb in MTT (this makes it easier to turn off
all messages from the typechecker as one can just set the debug value to
 False in Eval)
Merge remote-tracking branch 'origin/conv' into conv
rename MTT into TypeChecker
one more example in helix
remove dummy files