Make a pro file based project out of the photoviewer example

Having a .pro file project is necessary to be able to deploy to
Android. Further patches for Android support will be needed, but
this is the base.

Task-number: QTBUG-38122
Change-Id: I878ec1df50d7375ae9153f8a34f763b5678d7774
Reviewed-by: Mika Salmela <mika.salmela@digia.com>
Reviewed-by: Sami Makkonen <sami.makkonen@digia.com>
Reviewed-by: Tim Jenssen <tim.jenssen@digia.com>