key bind issue mouse scroll

Sorry for the delay on adding scroll input rebinds. It's now at the top of my to-do list. I've been back from vacation for a few weeks working on various things folks have request. Lots to do!

That said, zooming in/out is already hotkeyed to the scroll wheel, but you hold ctrl. So, ctrl+scroll wheel.

Obviously that's not exactly what you're requesting (you want it just to be scroll with no modifier), but I thought I'd mention just in case anyone doesn't know you can still zoom with the scroll wheel.