This makes VehicleComponents reusable from core plugin without
requiring override of prerequisiteSetup

virtual marks a method for inclusion on a v-table, but we don't want
the methods of classes that won't be inheritable to have a v-table,
we want, however, to issue a warning if somebody try to inherit
that specific class and reimplement those methods.

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>

- properties now hand off of main “autopilot” object in qml
- Added support for summary items through qml

Used for unit testing