CHANGELOG entry

Author: hargoniX

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Add a simple speaker demo for micro:bit V2.
 - Add Board struct following the pattern used in other nrf board support crates.
 - Add magnetometer example.
+- LEDs on the micro:bit V1 are now turned off per default
 
 ## [0.10.1] - 2021-05-25