code: @Override
      public void onSection(PdfWriter writer, Document document, float paragraphPosition, int depth, Paragraph title) {
          String anchorDst = "w" + (anchorId++);
          defineLocalDestinationOnFirstChunk(title, anchorDst);
          addEntry(title.getContent(), depth, pageNumber.pageInfos(), anchorDst);
      }
docs: Called when a Section is written.
  <br>
  <CODE>position</CODE> will hold the height at which the
  section will be written to.
  
  @param writer            the <CODE>PdfWriter</CODE> for this document
  @param document          the document
  @param paragraphPosition the position the section will be written to
  @param depth             the number depth of the Section
  @param title             the title of the section