Remove a checker from the list of registered checkers.

        @param checker: the checker to remove

def unregisterChecker(self, checker):
        """
        Remove a checker from the list of registered checkers.

        @param checker: the checker to remove
        """
        self.linter._checkers[checker.name].remove(checker)
        if checker in self.linter._reports:
            del self.linter._reports[checker]
        if checker in self.linter.options_providers:
            self.linter.options_providers.remove(checker)