Register a Linter class for file verification.

        :param linter:
        :return:

def register_linter(linter):
        """
        Register a Linter class for file verification.

        :param linter:
        :return:
        """
        if hasattr(linter, "EXTS") and hasattr(linter, "run"):
            LintFactory.PLUGINS.append(linter)
        else:
            raise LinterException("Linter does not have 'run' method or EXTS variable!")