AddFont(string family [, string style [, string file [, string dir]]])
FPDF_FONTPATH (si es que ha sido definida)
familystyleB: bold (negrita)
I: italic (cursiva)
BI o IB: bold italic (negrita cursiva)
filedir$pdf->AddFont('Comic', 'I');
$pdf->AddFont('Comic', 'I', 'comici.php');