Adds WirelessLANGroup.comments to all the required places

- [x] 1. Add the field to the model class
- [x] 2. Generate and run database migrations
- [NA] 3. Add validation logic to clean()
- [NA] 4. Update relevant querysets
- [x] 5. Update API serializer
- [x] 6. Add fields to forms
    - [x] wireless.forms.model_forms, create/edit (e.g. model_forms.py)
    - [x] wireless.forms.bulk_edit, bulk edit
    - [x] wireless.forms.bulk_import, CSV import
    - [NA] filter (UI and API)
- [x] 7. Extend object filter set
- [NA] 8. Add column to object table (Note: was already present)
- [x] 9. Update the SearchIndex
- [x] 10. Update the UI templates
- [x] 11. Create/extend test cases
    - [NA] models
    - [x] views
    - [NA] forms
    - [x] filtersets
    - [x] api
- [NA] 12. Update the model's documentation

netbox/wireless/search.py

@@ -21,6 +21,7 @@ class WirelessLANGroupIndex(SearchIndex):
         ('name', 100),
         ('slug', 110),
         ('description', 500),
+        ('comments', 5000),
     )
     display_attrs = ('description',)