Log Message:
Update to 0.4.0

Changelog:
0.3.x -> 0.4.0
- add support for unknown encoding files (ie. DOS file)
- add potential support for converting Lotus, ... documents,
- accept to convert all Lotus Wk1 files and Symphony Wk1 files,
- add support for Lotus Wk3 and Wk4 documents,
- add support for Quattro Pro Wq1 and Wq2 documents,
- only in debug mode, add pre-support for Lotus Wk5..., must allow to
  retrieve the main sheets content's with no formatting,
- add potential support for asking the document's password ( but do nothing )
- correct some compiler warnings when compiling in debug mode.