Buzzer API

[SheepSeb]

Pull Request Overview

This pull request continues the work done in #4 by @teodorobert

This pull request adds:

• a buzzer API resolves #1 , similar to the libtock-c version. The API provides a function that simulates a synchronous tone setting and also functions to register/unregister a listener, check for driver existence
• an example app which plays Ode of Joy
• a fake buzzer driver, for testing
• unit tests for the fake driver and for the user space library

Testing Strategy

This PR was tested with the unit tests and by running the example app on a microbit v2 board

TODO or Help Wanted

Feedback

Documentation Updated

• [x] no updates are required

[alexandruradovici]

@SheepSeb any updates?

[SheepSeb]

Upstream tock#470

[SheepSeb]

Merged into master