Material: Material appearance

Uses new material system for appearance

Each feature object now has a property called ShapeMaterial that
describes its physical properties. If it has a shape, it has a
material.

The ShapeColor attribute is replaced by a ShapeAppearance attribute.
This is a material list that describes all appearance properties, not
just diffuse color. As a list in can be used for all elements of a
shape, such as edges and faces.

A new widget is provided to allow the user to select materials in a
consistent fashion. It can also launch the material editor with its
more advanced capabilities.

src/Mod/PartDesign/Gui/ViewProviderDressUp.cpp

@@ -104,7 +104,7 @@ void ViewProviderDressUp::highlightReferences(const bool on)
             originalFaceColors = vp->DiffuseColor.getValues();
             std::vector<App::Color> colors = originalFaceColors;
 
-            PartGui::ReferenceHighlighter highlighter(base->Shape.getValue(), ShapeColor.getValue());
+            PartGui::ReferenceHighlighter highlighter(base->Shape.getValue(), ShapeAppearance.getDiffuseColor());
             highlighter.getFaceColors(faces, colors);
             vp->DiffuseColor.setValues(colors);
         }