Update vtu_save.h

Author: TimGoTheCreator

src/io/vtu_save.h

@@ -6,6 +6,8 @@
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 // GNU General Public License for more details.
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #pragma once
 #include <vector>