Make netbox-docker function with v2.4-beta1 again, fixes#84.
> The shell --plain option is deprecated in favor of -i python or --interface python.
> The shell --interface option now accepts python to force use of the “plain” Python interpreter.
https://docs.djangoproject.com/en/2.0/releases/1.10/#deprecated-features-1-10
Initializers are startup scripts for common tasks like creating custom
fields. These are problems many users of Netbox Docker potentially face
and are therefore worth sharing.
This changes the default configuration to be better prepared for
usage with container management platforms, such as Docker Swarm,
Kubernetes or OpenShift.
Closes#27.