GitLab

This allows to show which option is selected with defaults or with
different FQBNs.

For example:

    $ arduino-cli board details arduino:avr:nano
    Board name: Arduino Nano

    Option:     Processor                         cpu
                ATmega328P                      ✔ cpu=atmega328
                ATmega328P (Old Bootloader)       cpu=atmega328old
                ATmega168                         cpu=atmega168

or:

    $ arduino-cli board details arduino:avr:nano:cpu=atmega328old
    Board name: Arduino Nano

    Option:     Processor                         cpu
                ATmega328P                        cpu=atmega328
                ATmega328P (Old Bootloader)     ✔ cpu=atmega328old
                ATmega168                         cpu=atmega168