Scroller: Adds options to control scroll friction and velocity (1/2)

I recommend trying 25 for friction and 20 for velocity to
get and idea of what I was looking for.

Do we want to come up with an aokp preset to these?
Right now they are set to stock as default.

Change-Id: I6d15a6bbc25c0acef4928e5c2364de276e91610c