/// <summary>
 /// Adds a new user.
 /// </summary>
 /// <param name="sessionID">The sessionID of the current session</param>
 /// <param name="username">The username.</param>
 /// <param name="password">The password.</param>
 /// <param name="firstname">The firstname.</param>
 /// <param name="lastname">The lastname.</param>
 /// <param name="roles">The roles.</param>
 public void AddUser(string sessionID, string username, string password, string firstname, string lastname, List<string> roles)
 {
     UsersTableAdapter uta = new UsersTableAdapter();
     int id = (int)((decimal)(uta.InsertAndGetIdentity(username, password, "", firstname, lastname)));
     foreach (string role in roles)
     {
         RolesTableAdapter rta = new RolesTableAdapter();
         rta.Insert(id, role);
     }
 }