BIP39 Validator 1.0.0rc1

Pre-release version of BIP39 Validator 1.0.0. Be warned that this is alpha-quality software and may not even run.

Notable changes in this release:

- Driver program created
- API and docstrings created
- reStructuredText documentation created
- Well-formed test implemented
- Levenshtein distance test implemented
- Initial unique characters test implemented
- Maximum length test implemented