decl_hdf5 MPI-I/O Collective or Independent, fix #419

[jmorice91]

Possibility to choose parallel MPIIO pointer (COLLECTIVE/INDEPENDENT) for hdf5 in parallel.

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[jmorice91]

Previous review are in #494

[JAuriac]

OK.
Three minor comments to change.

[benoitmartin88]

My personal opinion: I think that all if/else blocks should use curly braces, even if there is only 1 line.

Suggested change

	if (0 > H5Pset_dxpl_mpio(xfer_lst, m_mpio)) handle_hdf5_err();
	if (0 > H5Pset_dxpl_mpio(xfer_lst, m_mpio)) {
	handle_hdf5_err();
	}

[benoitmartin88]

Suggested change

	if (m_direction == READ)
	do_read(ctx, h5_file, xfer_lst);
	else
	if (m_direction == READ) {
	do_read(ctx, h5_file, xfer_lst);
	} else {

[benoitmartin88]

Suggested change

	return dset_plist;
	return dset_plist;
	}