Fix SSL with HAProxy.

The current configuration of services is that if SSL is in use (signaled by
stunnel.connect_ip) we bind to 127.0.0.1 - which is great, but it breaks
simultaneous non-SSL due to there being no pass-through stunnel equivalent on
all the nodes. As an interim measure, teach stunnel to connect to the ctlplane
address instead. We will need this flexability in future anyway to deal with
mixed-mode configurations, but we don't yet have an SSL only configuration.

The change will permit SSL only by altering the Deployment object only - the
SSL config object should now be flexible enough to run in either mode (but as
yet on an all-one-way-or-the-other basis).

Change-Id: Ibac3dec1fe7b573029482fdd9ad2d2f6223fbce0
Merge "Fix SSL with HAProxy."