config+server+lnd_test: expose chan status manager config options

Exposes the three parameters that dictate
the behavior of the channel status manager:
 * --chan-enable-timeout
 * --chan-disable-timeout
 * --chan-status-sample-interval

server.go

@@ -3105,7 +3105,7 @@ func (s *server) watchChannelStatus() {
 	status := make(map[wire.OutPoint]activeStatus)
 
 	// We'll check in on the channel statuses every 1/4 of the timeout.
-	unchangedTimeout := cfg.InactiveChanTimeout
+	unchangedTimeout := cfg.ChanDisableTimeout
 	tickerTimeout := unchangedTimeout / 4
 
 	if unchangedTimeout == 0 || tickerTimeout == 0 {