BUG: Remove duplicate swig typemap for ItemVector.

Xdmf.i

@@ -292,6 +292,4 @@ swig -v -c++ -python -o XdmfPython.cpp Xdmf.i
 %include XdmfTime.hpp
 %include XdmfTopology.hpp
 %include XdmfTopologyType.hpp
-%include XdmfUnstructuredGrid.hpp
-
-%template(ItemVector) std::vector<boost::shared_ptr<XdmfItem> >;
+%include XdmfUnstructuredGrid.hpp
\ No newline at end of file