Before this change, the "context", "cluster", and "user" fields in generated kubeconfig YAML were always hardcoded to "pinniped". This could be confusing if you generated many kubeconfigs for different clusters.
After this change, the fields will be copied from their names in the original kubeconfig, suffixed with "-pinniped". This suffix can be overridden by setting the new `--generated-name-suffix` CLI flag.
The goal of this change is that you can distinguish between kubeconfigs generated for different clusters, as well as being able to distinguish between the Pinniped and original (admin) kubeconfigs for a cluster.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
