Add designer-examples.png
Add designer-examples.png

This file was missing (and referenced in the examples docs). I
copied it from the Qt 4.8 repository.

Change-Id: I872948200bf0c881a520c71b5d8c96b4609ce2ce
Reviewed-by: Paul Olav Tvete <97541fb6312d77f06e19078c7c70b2c1f75fb828@digia.com>

kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc