json: provide ToJSON method, returning std::unique_ptr<T>
json: provide ToJSON method, returning std::unique_ptr<T>

This is preferred way, while correctly handles object ownership
olifre/root,root-mirror/root,karies/root,olifre/root,karies/root,karies/root,karies/root,olifre/root,root-mirror/root,olifre/root,olifre/root,olifre/root,olifre/root,root-mirror/root,olifre/root,karies/root,root-mirror/root,olifre/root,olifre/root,olifre/root,root-mirror/root,root-mirror/root,root-mirror/root,karies/root,root-mirror/root,karies/root,karies/root,karies/root,root-mirror/root,karies/root,karies/root,root-mirror/root,root-mirror/root