- improve BMe extractor with new added classes.
- I have written a half of BME validator, but I gave up now.
* it takes too much time and I don't want to pay more on it. postpone it to next update.
* I annotate all of BMe validator code for future implementation.
* the improvement of BME json files (upgrade them to YAML format) also is postponed.
- change some interface in common.py. synchronize it to other modules using it.
