private void buttonDeleteZookeeper_Click(object sender, EventArgs e)
 {
     Zookeepers.DeleteZookeeper(sqlConnection, dataGridViewZoo, textBoxZookeeperName.Text, textBoxZookeeperSurname.Text);
 }
 private void buttonShowAllZookeepers_Click(object sender, EventArgs e)
 {
     Zookeepers.ShowAllZookeepers(sqlConnection, dataGridViewZoo);
 }