updated headers to comply to naming convention for header-ifdefs

[[Imported from SVN: r347]]

istl/ilu.hh

 // -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 // vi: set et ts=4 sw=2 sts=2:
-#ifndef __DUNE_ILU_HH__
-#define __DUNE_ILU_HH__
+#ifndef DUNE_ILU_HH
+#define DUNE_ILU_HH
 
 #include <math.h>
 #include <complex>

istl/istlexception.hh

 // -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 // vi: set et ts=4 sw=2 sts=2:
-#ifndef __DUNE_ISTLEXC_HH__
-#define __DUNE_ISTLEXC_HH__
+#ifndef DUNE_ISTLEXC_HH
+#define DUNE_ISTLEXC_HH
 
 #include <stdlib.h>
 

istl/operators.hh

 // -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 // vi: set et ts=4 sw=2 sts=2:
-#ifndef __DUNE_ISTLOPERATORS_HH__
-#define __DUNE_ISTLOPERATORS_HH__
+#ifndef DUNE_ISTLOPERATORS_HH
+#define DUNE_ISTLOPERATORS_HH
 
 #include <math.h>
 #include <complex>

istl/scalarproducts.hh

 // -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 // vi: set et ts=4 sw=2 sts=2:
-#ifndef __DUNE_SCALARPRODUCTS_HH__
-#define __DUNE_SCALARPRODUCTS_HH__
+#ifndef DUNE_SCALARPRODUCTS_HH
+#define DUNE_SCALARPRODUCTS_HH
 
 #include <math.h>
 #include <complex>