Fix scroll to page top

[bashkirtsevich]

Update navigation feature. Scroll page to top, when user click on nav node (lvl 1 header in navigator).

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[bashkirtsevich]

Also may be should add scrollTo(null) here?

[timaschew]

Please run these commands to trigger netlify deployment for this Pull Request:

git commit --amend --no-edit
git push --force

[solymosi]

I think setting auto2top to true achieves the same effect as this PR. As a result, this PR would essentially force-enable auto2top for everyone, nullifying the browser's auto scroll-restoration behavior when going back and forward in history.

I've submitted an alternative proposal in #744

[timaschew]

Closing in favor of #744
I've started a discussion regarding whether auto2top: false make sense.