[1/2] Left handed navbar during landscape mode

This patch allows for the navbar to be moved to the left side of the
screen during landscape mode. Left handed people are more used to this
option.

This patch must go with another patch that changes framework/base

Screenshot: http://i.imgur.com/jWqJcEV.png

Settings: Hide left handed nav option in tablet

AICP:
Modified it for AICP
PS2: Remove the preference for non-navbar devices also

Change-Id: I3c5e96ba45bf02ba4b15fab0965b49abc8c16c84