added #style method to runs

ts/docx/run/style.ts

@@ -0,0 +1,13 @@
+import { XmlAttributeComponent, XmlComponent } from "../xml-components";
+
+class StyleAttributes extends XmlAttributeComponent<{val: string}> {
+    protected xmlKeys = {val: "w:val"};
+}
+
+export class Style extends XmlComponent {
+
+    constructor(styleId: string) {
+        super("w:rStyle");
+        this.root.push(new StyleAttributes({val: styleId}));
+    }
+}