Maintenance release of rsync4j

Today, I made a maintenance release for my rsync4j library available: 3.1.2-16

Code-wise nothing changed, but all Windows executables and DLLs were updated, now based on openssh 8.0p1-2.

BTW If you are a company making use of openssh, please consider donating to the project, as this maintained by developers of the OpenBSD project. See the openssh homepage for details.