Scroll_smooth_offset is not working

Here a patch to add the two offset fields for a fixed header.

I just tested it.

Two new fields are added to the config page.

headingsOffset seems to work properly, while scrollSmoothOffset seems broken (or I don't understand how it should work). For example I tried adding 20 and it broke the smooth scrolling.

Actually, the headingsOffset doesn't brake the scrolling, but it doesn't look like it's doing anything either..
I tried from 20 to 120 and I saw no change.

Assuming the library itself works correctly, there might be work to do in this module.

Thanks for the work and review.
Can this be created as a merge request, and the mentioned issues looked into?

It seems that this patch has already found its way to version 2.x

I was to quick with my comment that this was already

Rerolled patch for version 2.x