private void Vehicles_DataGrid_MouseDoubleClick(object sender, MouseButtonEventArgs e)
        {
            var tmp    = (Vehicle)Vehicles_DataGrid.SelectedItem;
            var window = new VehicleWindow("Edit", tmp);

            window.ShowDialog();
            SetDataGrid();
        }
        private void AddVehicle_Click(object sender, RoutedEventArgs e)
        {
            var vehicle = new Vehicle();
            var add     = new VehicleWindow("Add new vehicle", vehicle);

            add.ShowDialog();

            what = "vehicles";
            SetDataGrid();
        }