fix [ bug #825 ] User first name not visible into users->perms
[ task #826 ] Increasing stock when deleting an invoice
Fix trans for  [ task #826 ] Increasing stock when deleting an invoice
Fix bug on update invoice line in PgSQL
Fix fix as Eldy wish it
Merge pull request #841 from FHenry/develop

fix [ bug #825 ] User first name not visible into users->perms