Merge branch 'fix/mpi-1-deprecation-warnings' into 'master'

[Warnings] Fix MPI 1 deprecation warnings (by switching to MPI 2).

See merge request !125

dune/istl/paamg/test/parallelamgtest.cc

@@ -214,8 +214,8 @@ int main(int argc, char** argv)
 {
   MPI_Init(&argc, &argv);
   MPI_Errhandler handler;
-  MPI_Errhandler_create(MPI_err_handler, &handler);
-  MPI_Errhandler_set(MPI_COMM_WORLD, handler);
+  MPI_Comm_create_errhandler(MPI_err_handler, &handler);
+  MPI_Comm_set_errhandler(MPI_COMM_WORLD, handler);
 
   int N=100;
 

dune/istl/test/matrixredisttest.cc

@@ -120,8 +120,8 @@ int main(int argc, char** argv)
 {
   MPI_Init(&argc, &argv);
   MPI_Errhandler handler;
-  MPI_Errhandler_create(MPI_err_handler, &handler);
-  MPI_Errhandler_set(MPI_COMM_WORLD, handler);
+  MPI_Comm_create_errhandler(MPI_err_handler, &handler);
+  MPI_Comm_set_errhandler(MPI_COMM_WORLD, handler);
   int procs;
   MPI_Comm_size(MPI_COMM_WORLD, &procs);