### SUMMARY

Update validate-modules to report messages using named error codes like `version-added` instead of error numbers like `E305`.

This would match the behavior of other tools we use, such as pylint, which have one named error code per rule. This will also make ignore entries much easier to read.

Doing this before 2.9 is released will avoid potential backwards compatibility issues with ignore entries in collections.

##### ISSUE TYPE

Feature Idea

##### COMPONENT NAME

validate-modules

path=self.object_path,
                        tracebk=trace
                    )
                if not errors and not traces:
                    missing_fragment = False
                    with CaptureStd():
                        try:
                            get_docstring(self.path, fragment_loader, verbose=True)
                        except AssertionError:
                            fragment = doc['extends_documentation_fragment']
                            self.reporter.error(
                                path=self.object_path,
                                code=303,
                                msg='DOCUMENTATION fragment missing: %s' % fragment
                            )
                            missing_fragment = True
                        except Exception as e:
                            self.reporter.trace(
                                path=self.object_path,
                                tracebk=traceback.format_exc()
                            )
                            self.reporter.error(
                                path=self.object_path,
                                code=304,
                                msg='Unknown DOCUMENTATION error, see TRACE: %s' % e
                            )
                    if not missing_fragment:
                        add_fragments(doc, self.object_path, fragment_loader=fragment_loader)
                    if 'options' in doc and doc['options'] is None:
                        self.reporter.error(