Make the CSV writer optional again
In commit 248436de by Axel (titled "Removed some pointers"), you reverted my change to make the CSV writer optional. For the DLL build of OCSR, it's crucial that writing CSV files is not mandatory.
I am re-introducing the pointer to the CSV writer now (in my branch). I'm using an old-school C pointer because I don't know much about smart pointers, so I hope that's okay for you as well.