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

This won't match `<iMg>` or any other mixed upper/lowercase combination. I'd suggest using the [re.I flag](https://docs.python.org/2/library/re.html#re.I) that makes the regular expression case insensitive.

    content = re.search(r'(<img.*?>)|(</?a[^>]*?>))', content, re.I)