* mw/kubernetes: resync to opts

Only used to initialize the cache that already has a dnsControlopts, so
remove it from the main kubernetes struct.

* Fix test

* mw/kubernetes: LabelSelector to options as well

Labels select is also only used for init. Don't carry it in the main
kubernetes struct.

* remove this test: can't happen

Caddyfile parser will only call setup when it sees kubernetes.

* erge gone wrong