add pdf and mobi libraries

inc/3rdparty/libraries/mpdf/examples/example40_MPDFI_thumbnails.php

@@ -0,0 +1,20 @@
+<?php
+
+include("../mpdf.php");
+
+$mpdf=new mPDF(); 
+$mpdf->SetImportUse();	
+
+$mpdf->Thumbnail('sample_orientation2.pdf', 4, 5);	// number per row	// spacing in mm
+
+$mpdf->WriteHTML('<pagebreak /><div>Now with rotated pages</div>');
+
+$mpdf->Thumbnail('sample_orientation3.pdf', 4);	// number per row	// spacing in mm
+
+
+$mpdf->Output();
+
+exit;
+
+
+?>