The patches required to use C++ STL

[KOLANICH]

These patches should be enough to use magic_enum library and std::string. For using CTRE other patches are needed, but they don't belong to this repo.

[CLAassistant]

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[KOLANICH]

It is likely these patches should be applied to other cores too.

[KOLANICH]

CLA won't be signed, but everyone can consider original parts of my contribution as licensed under Unlicense license.

[matthijskooijman]

Thanks for your contribution!

I believe this might be already solved in https://github.com/arduino/ArduinoCore-API, which should be the base of this core as well in the future (also see arduino/ArduinoCore-API#140 which makes some additional related changes).

[KOLANICH]

Thanks. Incorporated some changes from there.