added #font method to paragraph styles

ts/docx/run/formatting.ts

@@ -1,6 +1,7 @@
 import { Attributes, XmlComponent } from "../xml-components";
 export { Underline } from "./underline";
 export { SubScript, SuperScript } from "./script";
+export { RunFonts } from "./run-fonts";
 
 export class Bold extends XmlComponent {