configure kubectl autocomplete and alias k in jumpbox vm

[asaikali]

Improve the automation that creates the jumpbox vm to

1. alias k to kubectl
2. add bash completion

echo 'source <(kubectl completion bash)' >>~/.bashrc
echo 'alias k=kubectl' >>~/.bashrc
echo 'complete -o default -F __start_kubectl k' >>~/.bashrc

see https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/#enable-kubectl-autocompletion