Upcoming OpenSlide release will change library filename

[bgilbert]

The next OpenSlide release, 4.0.0, will include some incompatible API changes. Those are unlikely to affect you directly, but as a consequence, OpenSlide's soname will change. This will change the library filename to libopenslide-1.dll on Windows, libopenslide.1.dylib on macOS, and libopenslide.so.1 on Linux. Since OpenslideCs loads OpenSlide by filename on Windows and Linux, you may want to proactively add support for the new names so OpenslideCs will work with the new release.

For more information, see openslide/openslide#413. If you have any questions, please ask!