Disable leader election when LEADER_ELECTION_NAMESPACE is not set (#646)
Disable leader election when LEADER_ELECTION_NAMESPACE is not set (#646)

* Disable leader election when LEADER_ELECTION_NAMESPACE is not set

Debugging the controller is practically impossible, since it loses
the leader election lock when it's suspended for too long. This causes
the process to be terminated.

* Improve warning

smawson/istio,smawson/istio,smawson/istio,istio/istio,istio/istio,istio/operator,istio/operator,smawson/istio,istio/istio,smawson/istio,istio/istio,istio/operator,smawson/istio,istio/istio