Add a "--kubeconfig" global flag

[kastl-ars]

Is your feature request related to a problem? Please describe. I often work with multiple clusters. In my case, each has a separate kubeconfig file. Often this is because clusters are spun up for testing using e.g. vagrant+Ansible.

Having to export KUBECONFIG=... each time I need to target a different cluster is error prone and tedious.

Describe the solution you'd like Other tools, including kubectl and helm, allow using a --kubeconfig global flag, that uses the file given as argument to this flag as the kubeconfig for the command.

Describe alternatives you've considered

• exporting KUBECONFIG=...
• using things like kubie etc.