[IMP] website_forum: add plugin in editor for code management + karma check for editor options

- Task: https://www.odoo.com/web?debug=#id=8712&view_type=form&model=project.task&action=333&active_id=131
- Pad: https://pad.odoo.com/p/r.Mo2LPzffbGk1mjxD
Thanks for inform me, In here no necessary to pass uid as SUPERUSER_ID. I update in this branch and after rebase along with single commit.

```python
def _ckeditor_content_filter(self, forum, content):
        cr, uid, context = request.cr, request.uid, request.context
        user = request.registry['res.users'].browse(cr, uid, uid, context=context)
        forum = request.registry['forum.forum'].browse(cr, uid, forum.id, context=context)
```