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/Draft/draftfunctions/upgrade.py

@@ -227,7 +227,7 @@ def upgrade(objects, delete=False, force=None):
                 # of downgrade, nor do they have the same hashCode().
                 # Nevertheless, they still keep reference to their original
                 # colors, capture that in facecolors.
-                # Also, cannot use ShapeColor here, we need a whole array
+                # Also, cannot use ShapeAppearance here, we need a whole array
                 # matching the colors of the array of faces per object,
                 # only DiffuseColor has that
                 facecolors[0].extend(obj.ViewObject.DiffuseColor)