QtIFW

Add small auto test.

Also fix the implementation for append component in updater case
as well as adjust the documentation. The returned list contains
all components independent of the run mode.

Change-Id: I36523e13c33b9ca6de6e02fcc31e0f0d6606f65b
Reviewed-by: Jarek Kobus <jaroslaw.kobus@digia.com>