Added initial Melody Playback Ability

Now, controlled via MQTT a Playback of a melody can Start, Stop, Pause 
etc. 

Settings like speed, total duration, pauses etc can be set.

build/sketch/config.h

@@ -0,0 +1,11 @@
+#line 1 "C:\\Users\\espi_\\Documents\\Arduino\\vesper\\config.h"
+const char* ssid     = "SmartNet";
+const char* password = "smartpass";
+const char* hostname = "ESP32_mqtt_test";
+
+IPAddress ip(10, 98, 30, 150);
+IPAddress gateway(10, 98, 30, 1);
+IPAddress subnet(255, 255, 255, 0);
+
+#define MQTT_USER "esp32_vesper"
+#define MQTT_PASS "vesper"