update local.example.py, production.example.py
update README.md
Merge branch 'develop'
add authkey app
Merge branch 'develop'
    add authkey app
update .gitignore
update requirements.txt
add core/modules/widget.py
install celery
add widget app
add a celery task for widget app
update settings
update README.md
Merge branch 'develop'
update README.md
Merge branch 'develop'
update README.md
Merge branch 'develop'
[FEATURE] Broker
update README.md