clean Writers

We should spend some time on 'finalizing' moving to tomoscan volume. For various reason there is still some step to be done. Between those:

• removing the JP2Writer if possible
• remove HSTVolWriter if possible. Writing to xml was needed 'urgently' by id16b and saving metadata to several location was (and still not is) handled natively by the volume. We should think about the better way to handle this case.
• nabu.io.tiffwriter_zmm should be fully moved to tomoscan