[Log4cpp-devel] Updating for C++17 and 20

[<log...@li...>]

Hi - is log4cpp pretty much dead, or, just stable I guess. Well, parts won't compile under a C++ 17 - conforming compiler, not even when used as binaries (ie, even the headers are wrong) and for C++20 they're entirely forbidden: 

https://stackoverflow.com/questions/47727108/are-dynamic-exception-specifications-invalid-in-c17#47727338

The code compiles under 17 just fine if you simply remove all of the throw([...]) specifications, I can submit a pull request for that I guess. But we / someone should also get rid of the auto_ptr<>s. I thought of replacing them with unique_ptr<>s, but I'm afraid of subtle bugs due to possible different semantics. Any experts feel like taking that on? 

Jeff