Add support for setting S2 security keys via new environment variables. The NETWORK_KEY environment variable is replaced by with S0_LEGACY_KEY. NETWORK_KEY will be supported for now and removed at later time. All keys are optional from the container perspective, including NETWORK_KEY.
Other changes:
Remove empty environment variables from the Dockerfile
Update README.md with S2 details
Don't set undefined values in the configuration file
Add support for setting S2 security keys via new environment variables. The NETWORK_KEY environment variable is replaced by with S0_LEGACY_KEY. NETWORK_KEY will be supported for now and removed at later time. All keys are optional from the container perspective, including NETWORK_KEY.
Other changes: