Rel v4.0.0

• ArduinoJson to 7.2
• remove deprecated containskey()

• match WiFi event handler input types to Arduino core version

• Implement language translation for UI data
• update UI resources with lang translations Rus/Eng
• make /data dir with web resources, obsolete resources/data.zip
• Rework of Interface class, now JsonDocument could be manipulated in-place avoiding useless copies
  • Method JsonArray Interface::get_block() allows to get last section's block array
  • add new method Interface::make_new_object()
  • add Interface::json_frame_send() method, send accumulated data and clears memory while preserving sections stack
  • Interface methods return JsonObject on UI objects addition
  • reimplement Interface::button* methods
  • obsolete UIelement related objects

• refactor Interface::json* methods
  • added
  • Interface::json_block_get() to access block array
  • Interface::json_object_get() to access last added object
  • Interface::json_object_create() replaces Interface::make_new_object()
  • Interface::json_frame_add replaced with Interface::json_object_add
  • Interface::json_frame_* methods new return reference to JsonObjectwith a frame (in fact private json member)
• replace FrameSend::send() with const char* argument

• reduce EmbUI::save* metods, remove backup file save/load, use bare minimum

• change actionCallback_t prototype to accept json data via JsonObjectConst value

• remove all EmbUI config related methods
• obsolete SSDP related code

• fix Interface::_json_frame_next()