updated REST API and MQTT to use the same functionality

added heap as MQTT publish
updated User_Manual.md to latest changes
development build will have now always the same name because of static link from https://ahoydtu.de

src/web/web.h

@@ -40,6 +40,8 @@ class web {
 
         void serialCb(String msg);
 
+        void apiCtrlRequest(JsonObject obj);
+
     private:
         void onConnect(AsyncEventSourceClient *client);