QmlDesigner.QmlPupppet: Keeping the puppet from stealing focus on Mac

Defining QT_MAC_DISABLE_FOREGROUND_APPLICATION_TRANSFORM keeps the puppet
from stealing the focus of Qt Creator on Mac OS X and Qt 5.

Task-number: QTCREATORBUG-9418
Change-Id: Id0193b95d4c788ebe243773458645d1c584b2044
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Reviewed-by: Marco Bubke <marco.bubke@digia.com>
Remove unreachable link

Change-Id: Id14add2f8669c97d8608a7ed8455e63e50d3bcbe
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>