Create section properties section

src/file/document/body/section-properties/page-size/page-size.ts

@@ -0,0 +1,15 @@
+import { XmlComponent } from "file/xml-components";
+import { PageSizeAttributes } from "./page-size-attributes";
+
+export class PageSize extends XmlComponent {
+    constructor(width: number, height: number) {
+        super("w:pgSz");
+
+        this.root.push(
+            new PageSizeAttributes({
+                width: width,
+                height: height,
+            }),
+        );
+    }
+}