Option to disable STUN probing

[mroi]

The Moonlight client pings an external STUN server (stun.moonlight-stream.org) to determine the external IP address of the streaming setup. In a purely local setup, this should not be necessary for functionality and thus becomes a bit of a privacy leak: stun.moonlight-stream.org or anyone along the route can theoretically observe these pings and thus determine patterns in my usage of Moonlight.

I added a hidden preference to disable these pings to NSUserDefaults. It’s a boolean called disableSTUNProbe. Setting this to true prevents these STUN probes. This could become a user-exposed option in the future, but since it is a bit technical it might require more explanation. So far, this hidden preference is a useful starting point for me.