[MIGRATED] website_forum: migrated website_forum into new api + solved s...

...ome bugs

[IMP] website_forum: removed unnecessary imports
[IMP] website_forum: improved badges access for anonymous user
[IMP] wesite_forum: bug solved for ckeditor
use read_group and @api.multi instead of browsing all users and all their badges. Browsing all users and all their badges is very slow. use lazy=False when calling read_group to retrieve users and badge in the same call.