Option to invert mouse wheel commands for groupbox
Option to invert mouse wheel commands for groupbox

The option allows mouse-wheel up and down to invert next/prev group
selection.

Closes #381

andrewyoung1991/qtile,StephenBarnes/qtile,de-vri-es/qtile,qtile/qtile,zordsdavini/qtile,aniruddhkanojia/qtile,rxcomm/qtile,encukou/qtile,tych0/qtile,qtile/qtile,aniruddhkanojia/qtile,kynikos/qtile,EndPointCorp/qtile,EndPointCorp/qtile,flacjacket/qtile,kseistrup/qtile,jdowner/qtile,kopchik/qtile,kynikos/qtile,apinsard/qtile,soulchainer/qtile,farebord/qtile,tych0/qtile,ramnes/qtile,dequis/qtile,zordsdavini/qtile,soulchainer/qtile,andrewyoung1991/qtile,w1ndy/qtile,kseistrup/qtile,kiniou/qtile,flacjacket/qtile,StephenBarnes/qtile,ramnes/qtile,frostidaho/qtile,xplv/qtile,w1ndy/qtile,farebord/qtile,nxnfufunezn/qtile,himaaaatti/qtile,dequis/qtile,cortesi/qtile,de-vri-es/qtile,rxcomm/qtile,xplv/qtile,kopchik/qtile,jdowner/qtile,frostidaho/qtile,apinsard/qtile,nxnfufunezn/qtile,cortesi/qtile,encukou/qtile,himaaaatti/qtile,kiniou/qtile