fix reference section

docs/reference.md

@@ -22,15 +22,3 @@ control.inBackground(() => {
     
 });
 ```
-
-## Advanced
-
-```namespaces
-devices.tellCameraTo(MesCameraEvent.TakePhoto);
-bluetooth.onBluetoothConnected(() => {});
-```
-
-```package
-microbit-devices
-microbit-bluetooth
-```