Added Debian packaging

This MR will never be merged into master, it's only meant to be informal.

Some files where generated automatically and should not be considered. Some are empty but I think it could be handy to have them already available to help fixing future issues (instead of having to find which file should be created).

The important files are:

• debian/control
• debian/copyright
• debian/rules
• debian/changelog
• debian/README.Debian
• debian/patches/*