Rename superPlacement property to AttachmentOffset

The name Attachment Offset gives a better picture of what the
property does.

src/Mod/PartDesign/App/FeaturePrimitive.cpp

@@ -160,6 +160,11 @@ void FeaturePrimitive::onChanged(const App::Property* prop)
     FeatureAddSub::onChanged(prop);
 }
 
+void FeaturePrimitive::handleChangedPropertyName(Base::XMLReader &reader, const char* TypeName, const char* PropName)
+{
+    extHandleChangedPropertyName(reader, TypeName, PropName); // AttachExtension
+}
+
 PYTHON_TYPE_DEF(PrimitivePy, PartDesign::FeaturePy)
 PYTHON_TYPE_IMP(PrimitivePy, PartDesign::FeaturePy)
 

src/Mod/PartDesign/App/FeaturePrimitive.h

@@ -64,6 +64,7 @@ public:
         return PartDesign::FeatureAddSub::execute();
     }
 protected:
+    void handleChangedPropertyName(Base::XMLReader &reader, const char* TypeName, const char* PropName);
     //make the boolean ops with the primitives provided by the derived features
     App::DocumentObjectExecReturn* execute(const TopoDS_Shape& primitiveShape);
     Type primitiveType = Box;   

src/Mod/PartDesign/Gui/Utils.cpp

@@ -258,7 +258,7 @@ void fixSketchSupport (Sketcher::SketchObject* sketch)
                 Datum.c_str(), refStr.toStdString().c_str());
         Gui::Command::doCommand(Gui::Command::Doc,"App.activeDocument().%s.MapMode = '%s'",
                 Datum.c_str(), AttachEngine::getModeName(Attacher::mmFlatFace).c_str());
-        Gui::Command::doCommand(Gui::Command::Doc,"App.activeDocument().%s.superPlacement.Base.z = %f",
+        Gui::Command::doCommand(Gui::Command::Doc,"App.activeDocument().%s.AttachmentOffset.Base.z = %f",
                 Datum.c_str(), offset);
         Gui::Command::doCommand(Gui::Command::Doc,
                 "App.activeDocument().%s.insertObject(App.activeDocument().%s, App.activeDocument().%s)",

src/Mod/PartDesign/PartDesignTests/TestDatum.py

@@ -35,7 +35,7 @@ class TestDatumPoint(unittest.TestCase):
         self.DatumPoint.MapMode = 'ObjectOrigin'
         self.Body.addObject(self.DatumPoint)
         self.Doc.recompute()
-        self.assertEqual(self.DatumPoint.superPlacement.Base, App.Vector(0))
+        self.assertEqual(self.DatumPoint.AttachmentOffset.Base, App.Vector(0))
 
     def tearDown(self):
         #closing doc