Improve flag handling and help output for subcommands - an example might be best

[VestigeJ]

~> k3kcli -v
k3kcli version dev (HEAD)

~> k3kcli cluster create --servers 1 kicker --token YOUR_TOKEN_HERE
FATA[0000] empty cluster token

~> k3kcli cluster create --servers 1 kicker --token 'YOUR_TOKEN_HERE'
FATA[0000] empty cluster token

~> k3kcli cluster create --servers 1 kicker --token=YOUR_TOKEN_HERE
FATA[0000] empty cluster token

~> k3kcli cluster create --servers 1 kicker --token --help
FATA[0000] empty cluster token

~> k3kcli cluster create --servers 1 kicker --token moop
FATA[0000] empty cluster token

~> k3kcli cluster create --name kicker --token moop --servers 1

INFO[0000] Creating a new cluster [kicker]
FATA[0000] no matches for kind "Cluster" in version "k3k.io/v1alpha1" //offer to install controller here or install it automatically after checking if it's already in the cluster

~> k3kcli cluster create --help

NAME:
   k3kcli cluster create - Create new cluster

USAGE:
   k3kcli cluster create [command options] [arguments...]

OPTIONS:
   --kubeconfig value          Kubeconfig path [$KUBECONFIG]
   --name value                name of the cluster
   --servers value             number of servers (default: 1)
   --agents value              number of agents (default: 0)
   --token value               token of the cluster
   --cluster-cidr value        cluster CIDR
   --service-cidr value        service CIDR
   --persistence-type value    Persistence mode for the nodes (ephermal, static, dynamic) (default: "ephermal")
   --storage-class-name value  Storage class name for dynamic persistence type
   --server-args value         servers extra arguments
   --agent-args value          agents extra arguments
   --version value             k3s version (default: "v1.26.1-k3s1")