Implemented usermod for integration with smartnest.cz (#2800)

Co-authored-by: Christian Schwinne <dev.aircoookie@gmail.com>

wled00/usermods_list.cpp

@@ -132,6 +132,10 @@
 #include "../usermods/Si7021_MQTT_HA/usermod_si7021_mqtt_ha.h"
 #endif
 
+#ifdef USERMOD_SMARTNEST
+#include "../usermods/smartnest/usermod_smartnest.h"
+#endif
+
 #ifdef USERMOD_AUDIOREACTIVE
 #include "../usermods/audioreactive/audio_reactive.h"
 #endif
@@ -256,6 +260,10 @@ void registerUsermods()
   usermods.add(new Si7021_MQTT_HA());
   #endif
   
+  #ifdef USERMOD_SMARTNEST
+  usermods.add(new Smartnest());
+  #endif
+  
   #ifdef USERMOD_AUDIOREACTIVE
   usermods.add(new AudioReactive());
   #endif