Reorganize directories (#3462)

* 🚚 move files
* 🚚 rename doc folder to docs
* 🚚 rename test folder to tests

docs/examples/object.cpp

@@ -0,0 +1,28 @@
+#include <iostream>
+#include <nlohmann/json.hpp>
+
+using json = nlohmann::json;
+
+int main()
+{
+    // create JSON objects
+    json j_no_init_list = json::object();
+    json j_empty_init_list = json::object({});
+    json j_list_of_pairs = json::object({ {"one", 1}, {"two", 2} });
+
+    // serialize the JSON objects
+    std::cout << j_no_init_list << '\n';
+    std::cout << j_empty_init_list << '\n';
+    std::cout << j_list_of_pairs << '\n';
+
+    // example for an exception
+    try
+    {
+        // can only create an object from a list of pairs
+        json j_invalid_object = json::object({{ "one", 1, 2 }});
+    }
+    catch (json::type_error& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+}