text: Title: config.env database_url not working
  Body: i run a postgresql container in docker,
  and add this in config.env:
  `DATABASE_URL=postgresql://postgres:docker@localhost:5432/postgres`
  but every time i run:
  `python manage.py setup_dev`
  it will creates data-dev.sqlite
  
  ps:the db name and password is correct,i can use the command to connect:
  `psql -h localhost -U postgres -d postgres`
  