QtIFW

Fail if a component is a dependency but should be uninstalled.

Change-Id: Ie4fd05a46993a67d76c2b359db6483247be2d724
Reviewed-on: http://codereview.qt.nokia.com/3417
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Tim Jenssen <tim.jenssen@nokia.com>