Forbidden functions are not part of the coding style

[lodi-g]

Forbidden functions are not part of the coding style but are per-project and thus cannot be detected should not be detected in a general checker.

[ronanboiteau]

I think it's better for NormEZ to flag possible forbidden functions in its default behavior. It can really save a project. However I'm working on an option to disable forbidden functions warnings.

[lodi-g]

I was just talking about the Single Resposibility Principle - actually it may reveal useful to check for forbidden functions - forbidden functions are just not in the coding style so maybe you'd pick a more broad name and description.

[ronanboiteau]

Feature added by this pull request.