Make preferred install location option configurable.

Set this off by default becaues it's in a broken state and applies
to local installs.

Add a config parameter to hide/show "Preferred application install
location" which exists as a menu option in the ManageApplications.

Change-Id: Ib96c01038e38687fcc8b3d5d7b108c234804d6a1
(cherry picked from commit 198a64f5)