Add support for export to OpenDocument text and HTML for TextDocumentGenerator-based generators:
- EPub format
- Fictionbook format
- OOO.

This depends on Qt 4.5. Thanks to Qt Software (or wherever Thomas Z. works) for QTextDocumentWriter!

It wouldn't be too hard to make this work for plucker (.pdb) format, but that format doesn't work for me.
It would be very hard to make it work for other formats.