Since Mesos is no longer in your main repository and since we have
things like dynamic kubelet configuration in progress, we should
drop these undocumented, untested, private hooks.

cmd/kubelet/app/server.go::CreateAPIServerClientConfig
CreateAPIServerClientConfig::getRuntime
pkg/kubelet/kubelet_pods.go::getPhase

Also remove stuff from Dependencies struct that were specific to
the Mesos integration (ContainerRuntimeOptions and Options)

Also remove stale references in test/e2e and and test owners file