FIX nblignes not calculated after hook and hook can't modify this value. Usefull for modules

htdocs/core/modules/facture/doc/pdf_crabe.modules.php

@@ -250,6 +250,9 @@ class pdf_crabe extends ModelePDFFactures
 				global $action;
 				$reshook=$hookmanager->executeHooks('beforePDFCreation',$parameters,$object,$action);    // Note that $action and $object may have been modified by some hooks
 
+				// Set nblignes with the new facture lines content after hook
+				$nblignes = count($object->lines);
+				
 				// Create pdf instance
 				$pdf=pdf_getInstance($this->format);
                 $default_font_size = pdf_getPDFFontSize($outputlangs);	// Must be after pdf_getInstance