Update README.md

Author: MartyTremblay

README.md

@@ -11,7 +11,9 @@
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-hassio support for Airthings Wave, Airthings Wave Plus, and Airthings Wave Mini BLE environmental sensors.
+hassio support for Airthings Wave, Airthings Wave Plus, and Airthings Wave Mini BLE environmental sensors. 
+
+This component is cloudless and accomplishes this by communicating over bluetooth instead of using Airthings' cloud API.
 
 ![ScreenShot](ScreenShot.png)