Set VERAPP_EXIT_FAILURE_ON_STDERR_WRAPPER executable in VeraPPUtilities.cmake

We need it to be set in that scope as we use it in that file. Just include
it in src/
Merge pull request #3 from smspillaz/veracpp-cmake.fix_2

Set VERAPP_EXIT_FAILURE_ON_STDERR_WRAPPER executable in VeraPPUtilities.cmake