方便查看不同资源的容器镜像
https://github.com/redhatxl/kubectl-img

插件命名为：kubectl-img
目前仅简单实现一个 image 命令，用于查看不同资源对象 (deployments/daemonsets/statefulsets/jobs/cronjobs) 的名称，和对应容器名称，镜像名称。
支持 JSON 格式输出。
可以直接根据名称空间来进行查看对应资源。

$ kubectl img image -h
show k8s resource image

Usage:
  kubeimg image [flags]

Flags:
  -b, --cronjobs       show cronjobs image
  -e, --daemonsets     show daemonsets image
  -d, --deployments    show deployments image
  -h, --help           help for image
  -o, --jobs           show jobs image
  -j, --json           show json format
  -f, --statefulsets   show statefulsets image

Global Flags:
      --as string                      Username to impersonate for the operation
      --as-group stringArray           Group to impersonate for the operation, this flag can be repeated to specify multiple groups.
      --cache-dir string               Default cache directory (default "/Users/xuel/.kube/cache")
      --certificate-authority string   Path to a cert file for the certificate authority
      --client-certificate string      Path to a client certificate file for TLS
      --client-key string              Path to a client key file for TLS
      --cluster string                 The name of the kubeconfig cluster to use
      --context string                 The name of the kubeconfig context to use
      --insecure-skip-tls-verify       If true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure
      --kubeconfig string              Path to the kubeconfig file to use for CLI requests.
  -n, --namespace string               If present, the namespace scope for this CLI request
      --request-timeout string         The length of time to wait before giving up on a single server request. Non-zero values should contain a corresponding time unit (e.g. 1s, 2m, 3h). A value of zero means don't timeout requests. (default "0")
  -s, --server string                  The address and port of the Kubernetes API server
      --tls-server-name string         Server name to use for server certificate validation. If it is not provided, the hostname used to contact the server is used
      --token string                   Bearer token for authentication to the API server
      --user string                    The name of the kubeconfig user to use