Update current project URL on SourceForge

[ryandesign]

https://sourceforge.net/projects/libsmf/ says that development has moved to https://github.com/nilsgey/libsmf but that doesn't exist.

If this is now the new home of libsmf development, the SourceForge project should be updated to help people find it.

[diovudau]

This was over 10 years ago when the maintainership briefly changed to avoid deletion. No codechanges since then. I don't think it is reasonable to expect any active, especially not on the sourceforge project.

[trasz]

I’ll try to update it… once I figure out how :-)