Settings: SlimPie give user ability...

…to reduce trigger heights if IME keyboard shows (2/2)

Add a user option to reduce left and right trigger of SlimPie if
keyboard shows up
(especially usefull for swipe keyboard which most keyboards are
nowadays). Enabled
by default user can disable it in settings

Change-Id: I88a8294cd7a119a1498a26b55f05fa844d043589