Move the Joystick, Keyboard, and Mouse into a base class which handles
the operation/input, and a subclass which will implement the reporting
as a HID device via USB, Bluetooth Classic, or Bluetooth Low Energy (BLE).
Reduce copies of library code and makes maintainability much better.
Keyboard class now has support for non-en_US layouts, and documentation has
been added to the Mouse class.
Thanks to @rico0260 for letting me know about the update, and for the initial PR!
