Reorganize directories (#3462)

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

docs/examples/other_error.cpp

@@ -0,0 +1,29 @@
+#include <iostream>
+#include <nlohmann/json.hpp>
+
+using json = nlohmann::json;
+
+int main()
+{
+    try
+    {
+        // executing a failing JSON Patch operation
+        json value = R"({
+            "best_biscuit": {
+                "name": "Oreo"
+            }
+        })"_json;
+        json patch = R"([{
+            "op": "test",
+            "path": "/best_biscuit/name",
+            "value": "Choco Leibniz"
+        }])"_json;
+        value.patch(patch);
+    }
+    catch (json::other_error& e)
+    {
+        // output exception information
+        std::cout << "message: " << e.what() << '\n'
+                  << "exception id: " << e.id << std::endl;
+    }
+}