Gérer les abonnements aux bulletins

                                                                           
 88        88     ,ad8888ba,     88      a8P    88888888888   88888888ba   
 88        88    d8"'    `"8b    88    ,88'     88            88      "8b  
 88        88   d8'        `8b   88  ,88"       88            88      ,8P  
 88aaaaaaaa88   88          88   88,d88'        88aaaaa       88aaaaaa8P'  
 88""""""""88   88          88   8888"88,       88"""""       88""""""'    
 88        88   Y8,    "88,,8P   88P   Y8b      88            88           
 88        88    Y8a.    Y88P    88     "88,    88            88           
 88        88     `"Y8888Y"Y8a   88       Y8b   88            88