MedieInfo U2.11 Modular

Required libraries:
- ProjectUNION Core 0.3.0
- ProjectUNION MQTT 0.3.0
- PubSubClient
- Adafruit GFX
- Adafruit ST7735 and ST7789
- TJpg_Decoder

This project must not require:
- ProjectUNION DCC
- NmraDcc

First test:
1. Compile and note program/RAM size.
2. Confirm that no NmraDcc or esp_spi_flash warning appears.
3. Upload and test media, slides, MQTT/JSON, playlists and OTA.
