changed .C to .cpp in examples

Skin_surface_3/doc_tex/Skin_surface_3/SkinSurface3.tex

@@ -215,13 +215,13 @@ GHz, with 1 Gb of memory.
 \subsection{Meshing a skin surface}
 The following example shows the construction of a coarse mesh of the
 skin surface from an iterator range of weighted points and a shrink factor.
-\ccIncludeExampleCode{Skin_surface_3/skin_surface_simple.C}
+\ccIncludeExampleCode{Skin_surface_3/skin_surface_simple.cpp}
 
 \subsection{Meshing and subdividing a skin surface}
 This example extends the previous examples with a subdivision of the
 coarse mesh to obtain a better approximation. The use of the
 polyhedral items is not necessary, but gives a significant speedup.
-\ccIncludeExampleCode{Skin_surface_3/skin_surface_subdiv.C}
+\ccIncludeExampleCode{Skin_surface_3/skin_surface_subdiv.cpp}
 
 
 

Skin_surface_3/examples/Skin_surface_3/makefile

@@ -86,6 +86,6 @@ clean: \
 #                    suffix rules
 #---------------------------------------------------------------------#
 
-.C$(OBJ_EXT):
+.cpp$(OBJ_EXT):
 	$(CGAL_CXX) $(CXXFLAGS) $(OBJ_OPT) $<