switch from json to ordered_json

[gkriger]

From the perspective of casual user the most natural way of switching the code base to ordered_json seems to be replacing

using json = nlohmann::json;

with

using json = nlohmann::ordered_json; 

And the things mostly work. However, this:

json::object_t jobj({ { "product", "one" } });

does not compile however it compiles just fine with using json = nlohmann::json;
Compiler: Microsoft Visual C++ Compiler 16.4.29609.76 (x86_amd64) with c++11 flag.
lib release version 3.10.5

[nlohmann]

See #3343 - fixed with #3370.