Use body element when animating scroll in public page

In the public page the scroll container is the window instead of a div.
The $(window) object doesn't support animating the scroll property, so
the $('body') element is used instead.
Merge pull request #11590 from owncloud/publiclinkscrollanimatefix

Use body element when animating scroll in public page
Add app version to JS and CSS

This leads to the regeneration of the hash in case a single application is updated.

Fixes https://github.com/owncloud/core/issues/11374