- make use of environment and runtime info
- DfD: use host.docker.internal
- All other cases: use Docker network Gateway
- k3d-tools: based on alpine to have `getent` present
- `--cluster` flag parsed for `https://` prefix and node creation treated differently accordingly
- new `--network` string array flag to add the node to multiple networks (primary network when adding to a remote cluster)
- new `--token` flag to provide the cluster token
- before starting the cluster, gather environment info via tools node
- use hostIP/gatewayIP for DNS (iptables + resolv.conf updated in entrypoint script)
- revamp of custom entrypoint scripts
