MonadTall: Add option to place new windows at position of active window.
MonadTall: Add option to place new windows at position of active window.

Closes #980

ramnes/qtile,flacjacket/qtile,frostidaho/qtile,zordsdavini/qtile,soulchainer/qtile,tych0/qtile,ramnes/qtile,tych0/qtile,cortesi/qtile,qtile/qtile,kynikos/qtile,kynikos/qtile,qtile/qtile,zordsdavini/qtile,flacjacket/qtile,frostidaho/qtile,soulchainer/qtile,cortesi/qtile