pass ostream to writeSerialFile and writeParallelFile and set locale to "C"

dune/vtk/pvdwriter.hh

dune/vtk/pvdwriter.impl.hh

dune/vtk/vtktimeserieswriter.impl.hh

dune/vtk/vtkwriterinterface.hh

dune/vtk/vtkwriterinterface.impl.hh

dune/vtk/writers/vtkimagedatawriter.hh

dune/vtk/writers/vtkimagedatawriter.impl.hh

dune/vtk/writers/vtkrectilineargridwriter.hh

dune/vtk/writers/vtkrectilineargridwriter.impl.hh

dune/vtk/writers/vtkstructuredgridwriter.hh

dune/vtk/writers/vtkstructuredgridwriter.impl.hh

dune/vtk/writers/vtkunstructuredgridwriter.hh

dune/vtk/writers/vtkunstructuredgridwriter.impl.hh