feat(docker/node): more sovereign node utils

[xendarboh]

continuation from #86

• use .env to configure bind address
• sane defaults for volume dir prepared for persistence
• ensure startup script can handle node restarts, without wiping important config
  • ...more discovery required for proper behavior
• dockerignore docker-compose, etc
• consider packaging of files including: docker-compose.yml, scripts
• docs
  • add docker/node/README.md with instrux
    • copy env.example... etc
    • assign identifier
  • env.example comments