Code style changes.

Signed-off-by: Jean-Yves Tinevez <jean-yves.tinevez@pasteur.fr>
Allow specifying logger when saving to XML.

Signed-off-by: Jean-Yves Tinevez <jean-yves.tinevez@pasteur.fr>
Be more verbose when saving.

Signed-off-by: Jean-Yves Tinevez <jean-yves.tinevez@pasteur.fr>
Mute some Eclipse warnings.

Signed-off-by: Jean-Yves Tinevez <jean-yves.tinevez@pasteur.fr>