BUG : includes from VTK install

- BUG : the library vtkArrayIteratorIncludes.h was not installed in VTK but present in VTK build during the superbuild. We just put its content in vtkPVPostFilter.cxx since it was only including other librairies.

- BUG : correcting the windows bug of arrows for hide/show toolbox, by displaying ^ and v instead if WIN32