dev#160166 : Newsletters : Newletters may have custom Css

dev#160166 : task#177219

dev#160166 : Testing

dev#160166 : Ajout de tous les articles

dev#160166 : ajout de la possibilité d'ajouter une css custom

dev#160166 : fixing tests

dev#160166_newsletters : Fix choosing css uses file explorer

dev#166160_newsletters : reading customcss last

dev#160166 : Using $_SERVER['DOCUMENT_ROOT'] instead of ROOT_PATH

dev#160166 : Newsletter Widget : Fix OPAC display

dev#160166 : newsletters : unsubscribe by userid and not email

dev#160166 : newsletter : unsubscribe user even when email is empty

dev#160166 : Order and URL Absolute for main link

dev#160166 : newsletter : Fixing tests

dev#160166 : Newsletters : SORT_SELECTION should not transform collection

dev#160166 : newsletter : Fixing tests