added to_daily_usage_json()
added to_daily_usage_json()


Former-commit-id: e6c735ce8223f1e83fa900ecc568b092c777cbb9
Former-commit-id: 57d4284a606e81385fca81fa99a1f1d13808af33
dssg/wikienergy,dssg/wikienergy,dssg/wikienergy,dssg/wikienergy,dssg/wikienergy