Update outdated reference link in curvedgeflip.h to Wayback Machine archive

[lucaspalomodevelop]

In the file src/meshlabplugins/filter_trioptimize/curvedgeflip.h, there is a reference to the following paper:

http://www2.in.tu-clausthal.de/~hormann/papers/Dyn.2001.OTU.pdf

This link is now dead. However, the paper is still accessible via the Wayback Machine:

https://web.archive.org/web/20081031214049/http://www2.in.tu-clausthal.de/~hormann/papers/Dyn.2001.OTU.pdf

Please update the comment in the code to reference the archived link instead, so that future readers can access the paper.

Thank you!