public static bool Remove(Traveler t)
 {
     return _db.Delete(t);
 }
 public static Traveler Spawn()
 {
     Traveler t = new Traveler() { FirstName = "TestNom", LastName = "TestPrenom", Email = "*****@*****.**" };
     _db.Add(t);
     return t;
 }
 public static void Add(Traveler t)
 {
     _db.Add(t);
 }