Add section demo

demo/demo16.js

@@ -0,0 +1,28 @@
+const docx = require('../build');
+
+var doc = new docx.Document();
+
+var paragraph = new docx.Paragraph("Hello World");
+var paragraph2 = new docx.Paragraph("Hello World on another page").pageBreak();
+
+doc.addParagraph(paragraph);
+doc.addParagraph(paragraph2);
+
+doc.createParagraph("hello").pageBreak();
+
+var header = doc.createHeader();
+header.createParagraph("Header on another page");
+var footer = doc.createFooter();
+footer.createParagraph("Footer on another page");
+
+doc.addSection({
+  headerId: header.Header.referenceId,
+  footerId: footer.Footer.referenceId,
+  pageNumberStart: 1,
+  pageNumberFormatType: docx.PageNumberFormat.DECIMAL,
+});
+
+var exporter = new docx.LocalPacker(doc);
+exporter.pack('My Document');
+
+console.log('Document created successfully at project root!');