Fix: upgrade tcpdf with some fix

htdocs/includes/tcpdf/examples/example_001.php

htdocs/includes/tcpdf/examples/example_002.php

htdocs/includes/tcpdf/examples/example_003.php

htdocs/includes/tcpdf/examples/example_004.php

htdocs/includes/tcpdf/examples/example_005.php

htdocs/includes/tcpdf/examples/example_006.php

htdocs/includes/tcpdf/examples/example_007.php

htdocs/includes/tcpdf/examples/example_008.php

htdocs/includes/tcpdf/examples/example_009.php

htdocs/includes/tcpdf/examples/example_010.php

htdocs/includes/tcpdf/examples/example_011.php

htdocs/includes/tcpdf/examples/example_012.php

htdocs/includes/tcpdf/examples/example_013.php

htdocs/includes/tcpdf/examples/example_014.php

htdocs/includes/tcpdf/examples/example_015.php

htdocs/includes/tcpdf/examples/example_016.php

htdocs/includes/tcpdf/examples/example_017.php

htdocs/includes/tcpdf/examples/example_018.php

htdocs/includes/tcpdf/examples/example_019.php

htdocs/includes/tcpdf/examples/example_020.php