Data formats:
* Understand the password section
* Understand and document other file types (Data, Sheet, Agenda, etc)

Parser:
* Incorporate the replacement section. Stubs are already in place.
* Add additional file types.
* Add included objects

Generator:
* Add image support

Psiconv Generators:
* HTML: Verify generated code, to see whether it is HTML-3.2 compatible
* HTML4: Fallback on normal HTML for TextEd files might be replaced with
         true code. But is it worth it?
* RTF: Make it usable. Not nearly finished at the moment.
* IMAGE: support for special things like clipping is still lacking at the
         generator side. 

General:
* Many common values are returned as int. Perhaps change this to long,
  for better behaviour on very large files on some architectures?
* Use libaudiofile for audio conversions?
* Add generation of audio files.
