* add french c++ course
* fix blankline linting
* Update courses/free-courses-fr.md
Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>
* add to index
Co-authored-by: x0rld <git@x0rld.eu>
Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>