add developer conventions
add developer conventions


Former-commit-id: 7e0d43806e9b8ed749374caab9c4c74fdbaed75b
Former-commit-id: 2fbccb5eaefd7de3288348de75c54ac34d56e905
dssg/wikienergy,dssg/wikienergy,dssg/wikienergy,dssg/wikienergy,dssg/wikienergy