Add clientid to config

Allow the ability to configure the clientid in the configuration file

cmd/ot-browser/main.go

@@ -130,6 +130,9 @@ func (c *Config) ReadFile(filename string) error {
 	if val := mqtt.Key("remote").String(); val != "" {
 		c.mqttRemote = val
 	}
+	if val := mqtt.Key("clientid").String(); val != "" {
+		c.mqttClientId = val
+	}
 	www := cfg.Section("www")
 	if val := www.Key("remote").String(); val != "" {
 		c.wwwDir = val

cmd/ot-browser/receiver.go

@@ -117,6 +117,7 @@ func (mqtt *MQTTReceiver) mqttConnectionLost(client MQTT.Client, err error) {
 		if token.Wait() {
 			break
 		}
+		time.Sleep(2 * time.Second)
 	}
 	log.Printf("MQTT connection %s established", remote)
 }

ot-browser.ini.example

@@ -2,6 +2,7 @@
 
 [mqtt]
 remote = 127.0.0.1
+clientid = ot-browser
 
 [www]
 dir = ./www