QmlDesigner.PropertyEditor: Adding property to QmlModelNodeProxy

Change-Id: I8624cc5c5fc016a56f3dea18d0cca1620c6c4b86
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
QmlDesigner: move the beauty bottom rect inside the scrollview

Change-Id: I3cb85c6d7e9e259db7f4af28083d53539e5631b3
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
QmlDesigner: rename getting qml source path method

Change-Id: I354f3a76b18d83874c17f673ea42ebebe05b71ed
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>