Ajout des triggers et sequence d'auto incremente sur les clé primaire où
c'est nécessaire.
Merge branch 'master' of https://github.com/qays09/Projet_bd_depot_git.git
Merge branch 'master' of https://github.com/qays09/Projet_bd_depot_git.git
Merge branch 'master' of https://github.com/qays09/Projet_bd_depot_git.git
Merge branch 'master' of https://github.com/qays09/Projet_bd_depot_git.git
correction des return null pour les return void