QmlDesigner: For debug only the qt puppet should be used

Otherwise it is so easy to use a old puppet.

Change-Id: Ibe4cb8a783b88805db836fbb5874c349bb3976ea
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
QmlDesigner: Install the puppet to qt for debug

To prevent to have a puppet in qt which is selected first.

Change-Id: Ibe5efa1a10d1287eba17f8d29e9e77b2488d8b84
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>