Refactoring of DistributedGridIO_MeshFunction.

      MPI_Comm group=*((MPI_Comm*)(distrGrid->getCommunicationGroup()));

      MPI_File file;

        int ok=MPI_File_open( group,

      if( MPI_File_open( group,

            const_cast< char* >( fileName.getString() ),

            MPI_MODE_RDONLY,

            MPI_INFO_NULL,

                      &file );

        TNL_ASSERT_EQ(ok,0,"Open file falied");

            &file ) != 0 )

      {

         std::cerr << "Unable to open file " << fileName.getString() << std::endl;

         return false;

      }

		bool ret= load(file, meshFunction, data,0)>0;

      MPI_File_close(&file);

		return ret;

	}

    /* Funky bomb - no checks - only dirty load */