Warn on nonlocal addresses in configuration, PT results
With this branch we warn if we're listening for socks or dns on non-local addresses; we warn if we are configured with a non-local PT; and we reject any PTs that tell us they are running non-locally.
(The managed PT case is not a security hole, since PTs are trusted with our traffic anyway, and could just as easily relay it to a non-local address itself.)
Initial solution for #1636