[RPI] - missing nlohmann/json.hpp

[dimitre]

I've just made an old RPI runs to test OF and it is the first error

/home/pi/of/libs/openFrameworks/utils/ofJson.h:3:10: fatal error: nlohmann/json.hpp: No such file or directory
    3 | #include <nlohmann/json.hpp> // MSYS2 : use of system-installed include

My suggestion is we change apothecary libs to keep json.hpp inside nlohmann folder inside include, like

/of/libs/json/include/nlohmann/json.hpp

instead of

/of/libs/json/include/json.hpp

[ofTheo]

@dimitre thanks!

Looking at the nightly I do see it at that path:

Though I know other libs are missing currently.