As is convention in the k8s world, use zap for structured logging. For
development, OPERATOR_LOGGING=dev switches to a more human-readable output
than JSON.
Updates #502
Signed-off-by: David Anderson <danderson@tailscale.com>
Our reconcile loop gets triggered again when the StatefulSet object
finally disappears (in addition to when its deletion starts, as indicated
by DeletionTimestamp != 0). So, we don't need to queue additional
reconciliations to proceed with the remainder of the cleanup, that
happens organically.
Signed-off-by: David Anderson <danderson@tailscale.com>