Add kubeconfig flag to validate cluster command
Add kubeconfig flag to validate cluster command

Signed-off-by: vvbogdanov87 <24e13e83c9682bdcddfb5867f5078cf171d8ff7d@gmail.com>

kubernetes/kops,justinsb/kops,justinsb/kops,robinpercy/kops,kubernetes/kops,robinpercy/kops,kubernetes/kops,robinpercy/kops,robinpercy/kops,justinsb/kops