Made demo files into typescript files

demo/demo20.ts

@@ -0,0 +1,21 @@
+// Add custom borders to table cell
+// Import from 'docx' rather than '../build' if you install from npm
+import * as fs from "fs";
+import { BorderStyle, Document, Packer, Paragraph } from "../build";
+
+const doc = new Document();
+
+const table = doc.createTable(4, 4);
+table
+    .getCell(2, 2)
+    .addContent(new Paragraph("Hello"))
+    .CellProperties.Borders.addTopBorder(BorderStyle.DASH_DOT_STROKED, 3, "red")
+    .addBottomBorder(BorderStyle.DOUBLE, 3, "blue")
+    .addStartBorder(BorderStyle.DOT_DOT_DASH, 3, "green")
+    .addEndBorder(BorderStyle.DOT_DOT_DASH, 3, "#ff8000");
+
+const packer = new Packer();
+
+packer.toBuffer(doc).then((buffer) => {
+    fs.writeFileSync("My Document.docx", buffer);
+});