docs: main monorepo README

Author: eRgo35

README.md

@@ -1 +1,7 @@
-# esp32-playground
+# ESP32 Playground
+
+This repo contains two projects, a simple example program of how to connect an ESP32 to the display through the SPI interface, and a more advanced program working as an ESP32 quiz device.
+
+[SPI Display Example](https://github.com/rust-community-pl/esp32-playground/tree/main/spi_display_example)
+
+[MQTT Quiz Example](https://github.com/rust-community-pl/esp32-playground/tree/main/mqtt_example)