Ds1820 HADiscovery (#621)

* DS18b20 HADiscovery
* Allow Multiple DS18b20 Sensors
* Optimize Bus Scan
* Update Docs

Co-authored-by: Jonathan Michael Wells <jonathan-wells@oist.jp>

docs/use/sensors.md

@@ -19,4 +19,14 @@ You will receive the HTU21 sensor readings every TimeBetweenReadinghtu21 (set in
 
 `home/OpenMQTTGateway/CLIMAtoMQTT/htu {"tempc":25.34064,"tempf":77.61314,"hum":56.53052}`
 
-If you don't want to resend values that haven't changed you can set htu21_always = false in config_HTU21.h
+If you don't want to resend values that haven't changed you can set htu21_always = false in config_HTU21.h
+
+### DS18x20
+You will receive the DS18x20 sensor readings every DS1820_INTERVAL_SEC (set into config_DS1820.h) (60s by default).
+Each sensor will be published under the following topic using each sensors' address.
+
+`home/OpenMQTTGateway/CLIMAtoMQTT/ds1820/0x0000000000000000 {"temp":27.8,"unit":"C","type":"DS18B20","res":"12bit\n","addr":"0x28616411907650bc"}`
+
+The units for temperature readings are sent in Celcius by default can be changed to ferenheight by setting DS1820_FAHRENHEIT = true in in config_DS1820.h
+
+If you don't want to resend values that haven't changed you can set DS1820_ALWAYS = false in config_DS1820.h