PartDesign: remove SubShapeBinder.Support hidden status

Change Immutable status to ReadOnly, which makes it easy to set value
in script, but still block editing in property view by default. This is
to discourage user editing support using property editor, because
SubShapeBinder requires relative link correction.

src/Mod/PartDesign/App/ShapeBinder.cpp

@@ -276,9 +276,8 @@ PROPERTY_SOURCE(PartDesign::SubShapeBinder, Part::Feature)
 
 SubShapeBinder::SubShapeBinder()
 {
-    ADD_PROPERTY_TYPE(Support, (0), "",(App::PropertyType)(App::Prop_Hidden|App::Prop_None),
-            "Support of the geometry");
-    Support.setStatus(App::Property::Immutable,true);
+    ADD_PROPERTY_TYPE(Support, (0), "",(App::PropertyType)(App::Prop_None), "Support of the geometry");
+    Support.setStatus(App::Property::ReadOnly, true);
     ADD_PROPERTY_TYPE(Fuse, (false), "Base",App::Prop_None,"Fuse solids from bound shapes");
     ADD_PROPERTY_TYPE(MakeFace, (true), "Base",App::Prop_None,"Create face using wires from bound shapes");
     ADD_PROPERTY_TYPE(ClaimChildren, (false), "Base",App::Prop_Output,"Claim linked object as children");