add support for experimental option "prefer-bundled-bin"

[matteyeux]

Add support for experimental option "prefer-bundled-bin"

Summary

This pull request adds support for the experimental option prefer-bundled-bin to use bundled iptables instead of the OS iptables (which can be buggy see: https://docs.k3s.io/advanced#old-iptables-versions)

It wil be then added to the k3s config :

---

cluster-init: true
default-local-storage-path: /opt/storage
disable-network-policy: true
flannel-backend: none
node-label:
- group=vm
prefer-bundled-bin: true <--- this one

Closes #213

[matteyeux]

@onedr0p thank you for merging my PR, any plan to make a new release ?

[onedr0p]

I'm sure one will be made eventually, however in the meantime you can pin the role in your galaxy config file to branch and sha.