Check stunnel.connect_host not stunnel.connect_ip

The various service configurations all check for
stunnel.connect_ip as part of the configuration for
enabling stunnel. This variable doesn't exist in any
template. However stunnel.connect_host exists in
ssl_source.yaml

Change-Id: Iee4dd33d5afde211f669346005c36f88c9ebeae2
Depends-On: I25c4bb09cf28a3728e959d4dd583af26a602ad90
Closes-Bug: #1391926
Merge "Check stunnel.connect_host not stunnel.connect_ip"