[sch/brd] Fix trackpad zooming issues

[abetusk]

On some trackpads zoom goes haywire. Figure out how to make these input devices zoom properly so the user doesn't have to resort to keyboard shortcuts.

priority: medium
estimate: 3

[abetusk]

What a nightmare:

jquery/jquery-mousewheel#36
http://stackoverflow.com/questions/12486141/check-if-user-is-scrolling-with-trackpad/31195419#31195419

[abetusk]

I don't think this is possible with current technology. For reference, there's this? https://github.com/jquery/PEP.

Closing as there's not much I can do.