Reduce initial log level.
Rework fuzzy check module.

- Now all checks are organized to rules.
- Allow to specify read_only rules to avoid problems on learning.
- Use better normalizer for fuzzy module and it now returns values
  from 0 to 1.0 (like bayes does).
- Update configuration accordingly.
- Drop legacy configuration support.
- Detect tanh as well and provide some reasonable (linear) fallback.
Sync with libucl.