publish libraries to avoid users to have to download them one by one

lib/DHT-sensor-library/README.md

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+This is an Arduino library for the DHT series of low cost temperature/humidity sensors.
+
+Tutorial: https://learn.adafruit.com/dht
+
+To download. click the DOWNLOADS button in the top right corner, rename the uncompressed folder DHT. Check that the DHT folder contains DHT.cpp and DHT.h. Place the DHT library folder your <arduinosketchfolder>/libraries/ folder. You may need to create the libraries subfolder if its your first library. Restart the IDE.
+
+# Adafruit DHT Humidity & Temperature Unified Sensor Library
+
+This library also includes an optional class for the
+[DHT humidity and temperature sensor](https://learn.adafruit.com/dht/overview)
+which is designed to work with the [Adafruit unified sensor library](https://learn.adafruit.com/using-the-adafruit-unified-sensor-driver/introduction).
+
+You must have the following Arduino libraries installed to use this class:
+
+- [Adafruit Unified Sensor Library](https://github.com/adafruit/Adafruit_Sensor)