[FIX] website_forum:
   Use if_dom_contains to check if we need to load js
   Fix bug where _tag_to_write_vals was called like old API but model converter was new api
   Move IsKarmaValid and Load CKE only in website_forum context
[FIX] point_of_sale: remove a confusing partial implementation of UoS
[FIX] website_forum:
   Remove useless document ready
   Add select2 to frontend to allow public user to use tags