[Mesh Python] Mesh.show() returns python object, update documentation for Mesh.show(), Part.show(), and Points.show()

src/Mod/Mesh/App/AppMeshPy.cpp

@@ -82,7 +82,7 @@ public:
         add_varargs_method("show",
                            &Module::show,
                            "show(shape,[string]) -- Add the mesh to the active document or create "
-                           "one if no document exists.");
+                           "one if no document exists.  Returns document object.");
         add_varargs_method("createBox", &Module::createBox, "Create a solid mesh box");
         add_varargs_method("createPlane", &Module::createPlane, "Create a mesh XY plane normal +Z");
         add_varargs_method("createSphere", &Module::createSphere, "Create a tessellated sphere");
@@ -311,8 +311,7 @@ private:
         }
         // copy the data
         pcFeature->Mesh.setValue(*mo);
-
-        return Py::None();
+        return Py::asObject(pcFeature->getPyObject());
     }
     Py::Object createBox(const Py::Tuple& args)
     {

src/Mod/Part/App/AppPartPy.cpp

@@ -425,7 +425,8 @@ public:
             "read(string) -- Load the file and return the shape."
         );
         add_varargs_method("show",&Module::show,
-            "show(shape,[string]) -- Add the shape to the active document or create one if no document exists."
+            "show(shape,[string]) -- Add the shape to the active document or create one if no document exists.\n"
+            "Returns document object."
         );
         add_varargs_method("getFacets",&Module::getFacets,
             "getFacets(shape): simplified mesh generation"

src/Mod/Points/App/AppPointsPy.cpp

@@ -55,7 +55,7 @@ public:
         add_varargs_method("show",
                            &Module::show,
                            "show(points,[string]) -- Add the points to the active document or "
-                           "create one if no document exists.");
+                           "create one if no document exists.  Returns document object.");
         initialize("This module is the Points module.");  // register with Python
     }