Fix docker image build and installtion

[winkidney]

• Remove complex configuration, users should edit configuration-file to change them
• Keep some simple configuraton in command-line and ENVs
• Refactor tests
• To make it easier for us to change config, move local_settings.py out of docker and mounted to docker
• Support docker-compose
• Use gunicorn instead of uwsgi because it's more simple
• To make the structure less complex, remove supervisord (and it doesn't support python3)
• About "HTTPS" support: Should be detected by Django instead of changing it manually, it's a bug for us to host it by docker with host like "localhost", we may use "X-Forward-For" to generate the host-path.

[winkidney]

@overshard Please help to review if you have free time : )

[tsmsogn]

Great works! 🎉