[Gzz] Serializing enfilades

[b . fallenstein]

Hi,

Enfilade1Ds implement java.io.Serializable, and thus it should be possible
to save them through Java serialization. Anybody noticed this is not the case?
Reason is that they contain Span objects. First thing is that Spans do not
implement Serializable-- dunno whether Java will complain about this; second
and more important thing is that we need to save the scrollblocks before we
can serialize spans.

I have no idea how this should work. I'm inclined to think it might be
better to have a save() method in Enfilade1D that would save the scrollblocks 
and
return a serializable representation of the enfilade (would have to have a
corresponding load() in Enfilade1D.Maker).

Saving the scrollblocks should be an explicit action, IMHO-- serializing a
serializable object IMO doesn't qualify for that (I'd expect it not to modify
any system state).

So what do we do?

- Benja