Add MQTT last will testament implementation

#30

OpenMQTTGateway.ino

@@ -71,14 +71,14 @@ boolean reconnect() {
   while (!client.connected()) {
     trc(F("Attempting MQTT connection...")); //F function enable to decrease sram usage
     #ifdef mqtt_user
-      if (client.connect(GatewayName, mqtt_user, mqtt_password)) { // if an mqtt user is defined we connect to the broker with authentication
+      if (client.connect(Gateway_Name, mqtt_user, mqtt_password, will_Topic, will_QoS, will_Retain, will_Message)) { // if an mqtt user is defined we connect to the broker with authentication
       trc(F("connected with authentication"));
     #else
-      if (client.connect(GatewayName)) {
+      if (client.connect(Gateway_Name, will_Topic, will_QoS, will_Retain, will_Message)) {
       trc(F("connected without authentication"));
     #endif
     // Once connected, publish an announcement...
-      client.publish(GatewayAnnouncementTopic,GatewayAnnouncementMsg);
+      client.publish(will_Topic,Gateway_AnnouncementMsg);
       //Subscribing to topic
       if (client.subscribe(subjectMQTTtoX)) {
         trc(F("subscription OK to"));

User_config.h

@@ -35,6 +35,12 @@ CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFT
 #define mqtt_user "your_username" // not compulsory only if your broker needs authentication
 #define mqtt_password "your_password" // not compulsory only if your broker needs authentication
 #define mqtt_port 1883
+#define Gateway_Name "OpenMQTTGateway"
+#define will_Topic "home/OpenMQTTGateway/LWT"
+#define will_QoS 0
+#define will_Retain true
+#define will_Message "Offline"
+#define Gateway_AnnouncementMsg "Online"
 
 // Update these with values suitable for your network.
 #ifdef ESP8266 // for nodemcu, weemos and esp8266
@@ -54,10 +60,6 @@ CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFT
 #define time_avoid_duplicate 3000 // if you want to avoid duplicate mqtt message received set this to > 0, the value is the time in milliseconds during which we don't publish duplicates
 
 //MQTT definitions
-//RF MQTT Subjects
-#define GatewayName "OpenMQTTGateway"
-#define GatewayAnnouncementTopic "OpenMQTTGateway connected"
-#define GatewayAnnouncementMsg "hello broker!"
 // global MQTT subject listened by the gateway to execute commands (send RF, IR or others)
 #define subjectMQTTtoX "home/commands/#"
 
@@ -69,8 +71,8 @@ CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFT
 #define RFprotocolKey "433_" // protocol will be defined if a subject contains RFprotocolKey followed by a value of 1 digit
 #define RFpulselengthKey "PLSL_" // pulselength will be defined if a subject contains RFprotocolKey followed by a value of 3 digits
 //IR MQTT Subjects
-#define subjectIRtoMQTT "home/sensors/ir"
 #define subjectGTWIRtoMQTT "home/sensors/ir"
+#define subjectIRtoMQTT "home/sensors/ir"
 #define subjectMQTTtoIR "home/commands/MQTTtoIR"
 /*
 RF supported protocols