some cleanup to make the repository cooler
- move some old stuff in
oldstuff/, it's a kind of purgatory before potential deletion
please give a comment about the name of this directory, I was lacking some inspiration
- rename the appveyor file as a dot file (it's supported by appveyor), it is used in any way?
- a lot of readme improvements
the move of old files would make the netradiant gitlab homepage more usable, not requiring to scroll so many useless lines before getting to readme