Rename Apple touch icon and add `<link>` in the HTML.

See https://github.com/h5bp/html5-boilerplate/commit/345925f04384b59929d8d39ba428cef548921408
Mark project as private.

We don't plan to push the package to npm.
Fix a few ARIA related issues.
Remove `role=button` that was added accidentally in previous commit.
Update dependencies.
Tweak mobile view.
Add a dropdown navbar menu and icons.