Thanks for the pull request! It's a huge one, and it'll take me a while to get through it all when I get back from vacation, but I can tell you right now that I'm not going to merge all the commits. The CMake conversion is one such thing.
Feel free to merge as you like.
I found quite some bugs (using valgrind and further testing) when implementing mDNS support in https://github.com/open62541/open62541
Thanks for the pull request! It's a huge one, and it'll take me a while to get through it all when I get back from vacation, but I can tell you right now that I'm not going to merge all the commits. The CMake conversion is one such thing.