Added Basic MQTT Support and JSON Deserialization

JSON_functions.hpp

@@ -0,0 +1,26 @@
+#pragma once
+
+void reconstr (String payload) {
+  JsonDocument doc;
+
+  DeserializationError error = deserializeJson(doc, payload);
+
+  if (error) {
+    Serial.print("deserializeJson() failed: ");
+    Serial.println(error.c_str());
+    return;
+  }
+
+  // EXAMPLE PAYLOAD. CHANGE THIS TO THE APPROPRIATE ONE.
+  int a = doc["a"];
+  bool b = doc["b"];
+  float c = doc["c"];
+  Serial.println("The payload received contains: ");
+  Serial.print("a: ");
+  Serial.print(a);
+  Serial.print("  b: ");
+  Serial.print(b);
+  Serial.print("  c: ");
+  Serial.println(c);
+  
+}