Fix RetryPeersNow, move startup logging, don't set TUN address if not available

src/tun/tun_darwin.go

@@ -32,7 +32,10 @@ func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
 	} else {
 		tun.mtu = 0
 	}
-	return tun.setupAddress(addr)
+	if addr != "" {
+		return tun.setupAddress(addr)
+	}
+	return nil
 }
 
 // Configures the "utun" adapter from an existing file descriptor.