Fix high dpi node motion issues

[QcFe]

Hey, thanks for developing this amazing project!
I normally use a high density display and noticed the mouse behaved weirdly, I think it's what described in #20.
This should fix, hopefully

[newcat]

Thanks for the PR and sorry for replying late. I just checked and this change indeed solves the issue in Chrome. But we then get the wrong behaviour in Firefox 😄 I am going to merge it anyway, since Chrome has a higher market share, so more people benefit from Baklava running properly in Chrome than in Firefox. Since I do want to avoid browser detection, I will try to find out, which browser is not spec-compliant and open an issue in the respective bugtracker as soon as I have enough information.

[QcFe]

No problem!
Heh, my super bad, I forgot to chech if everything was working on Firefox. I trusted a bit too much what I found on the w3c and caniuse...
At least, indeed, this way the bug will be encountered by a smaller user base. I'll try to find more information about this when I get time.
Thank you for merging my PR btw!

[code-is-art]

This doesn't work for me and I have to revert it to work on both Chrome and Firefox on OSX . Maybe this should be an optional setting.