Components: Implement Menubar component

Problem/Motivation

Implement Menubar component:
https://nl-design-system.github.io/rvo/docs/componenten/menubar/

So that we construct this example page:
https://nl-design-system.github.io/rvo/iframe.html?args=&id=pagina-s-exp...

Proposed resolution

- Make a SDC for the Menubar component
- Use this component in page.html.twig