Add Homie for ESP8266 to 3rd party libs in docs

Author: marvinroger

doc/libraries.md

@@ -147,6 +147,7 @@ Libraries that don't rely on low-level access to AVR registers should work well.
 - [DimSwitch](https://github.com/krzychb/DimSwitch) - Control electronic dimmable ballasts for fluorescent light tubes remotely as if using a wall switch.
 - [Encoder](https://github.com/PaulStoffregen/Encoder) - Arduino library for rotary encoders. Version 1.4 supports ESP8266.
 - [esp8266_mdns](https://github.com/mrdunk/esp8266_mdns) - mDNS queries and responses on esp8266. Or to describe it another way: An mDNS Client or Bonjour Client library for the esp8266.
+- [Homie for ESP8266](https://github.com/marvinroger/homie-esp8266) - Arduino framework for ESP8266 implementing Homie, an MQTT convention for the IoT.
 - [NeoPixel](https://github.com/adafruit/Adafruit_NeoPixel) - Adafruit's NeoPixel library, now with support for the ESP8266 (use version 1.0.2 or higher from Arduino's library manager).
 - [NeoPixelBus](https://github.com/Makuna/NeoPixelBus) - Arduino NeoPixel library compatible with ESP8266. Use the "DmaDriven" or "UartDriven" branches for ESP8266. Includes HSL color support and more.
 - [PubSubClient](https://github.com/Imroy/pubsubclient) - MQTT library by @Imroy.