More builds

We need to integrate in our CI more compilers and different compiler versions to be more robust!

• Add Clang versions 12 and 15.
• Add G++ versions 10 and 12 (default is 11 for Ubuntu 22.04).
• Correct code to build on all the above.
• Make setup.py work with Windows (fixes aidge#13 (closed)).

Adding older versions would require to add older apt repositories to the Ubuntu distrib. Not a big issue with Docker, but does it worth it? We can specify a minimum compiler version. Supporting older versions may require more work.