Allow to redefine TCPDF object

Sometimes we need create TCPDF object with modified initial arguments.
This change allow rewrite only createExternalWriterInstance() in user defined TCPDF class.

Author: SailorMax

src/PhpWord/Writer/PDF/TCPDF.php

@@ -36,6 +36,20 @@ class TCPDF extends AbstractRenderer implements WriterInterface
      */
     protected $includeFile = 'tcpdf.php';
 
+	/**
+     * Gets the implementation of external PDF library that should be used.
+     *
+     * @param string $orientation Page orientation
+     * @param string $unit Unit measure
+     * @param string $paperSize Paper size
+     *
+     * @return \TCPDF implementation
+     */
+    protected function createExternalWriterInstance($orientation, $unit, $paperSize)
+    {
+        return new \TCPDF($orientation, $unit, $paperSize);
+    }
+
     /**
      * Save PhpWord to file.
      *
@@ -50,7 +64,7 @@ public function save($filename = null)
         $orientation = 'P';
 
         // Create PDF
-        $pdf = new \TCPDF($orientation, 'pt', $paperSize);
+        $pdf = $this->createExternalWriterInstance($orientation, 'pt', $paperSize);
         $pdf->setFontSubsetting(false);
         $pdf->setPrintHeader(false);
         $pdf->setPrintFooter(false);