The board has a second SPI bus wired up for communication with two RFID readers
if needed.
However, the code only provided a constructor with no arguments, preventing
the use of a second instance on the different bus.
Update the constructor and the definitions to allow changing the chip select
and SPI bus used when creating an RFID reader.
Introduce the Speaker class to play audio from the SD card when detecting
tags.
The only audio supported is WAV.
Audio playback is handled via interrupts, so it might try to read from the
SD card at the same time as the LCD class is trying to read new frames.
Update the LCD animation code to temporarily disable audio interrupts while
reading from the SD card.
sendComment cannot send more than 62 bytes, as limited by the HID report.
Sending more is prevented by vsnprintf, but change the function signature
to make it explicit that the array passed to it should be at most 62 bytes.
Add support for the LCD and using it for displaying animations.
Animations are automatically played if available for the ID of the
detected tag.
The code should support adding other kind of animations, for tags being
removed or for other UI interactions for example.
Implement a set of functions to create messages following the protocols
defined in the README for communication.
Handle HID, which is used to communicate with the interactive application.
Update README with details on the message structures.
Add a new class to handle the RFID module and associated data
in order to track active tags.
Update main with RFID initialization and a minimal usage to
check it is working as expected.
