Ignore exceptions

[breml]

I would like to use wwhrd in our CI pipeline and I would like to have it silent (with -q), that is without any output, if there are no license violations to take care of. This is, if an exception is granted by adding it to .wwhrd.yml and the flag -q is given, I would like to have no output.

Would you accept a PR to add this functionality? Should this be implemented as an additional flag to maintain the backwards compatibility?

[frapposelli]

I think we should probably just raise the default log level to Error for the -q flag, this would make a run with exceptions silent.