The Gitlab will upgrade to latest version for security in the Oct 7th (9:00 ~ 12:00 UTC+8), during the time, the Gitlab site will be offline.
We add a Makefile and a configuration file to automate the generation of
README.pdf with pandoc.
Also, update the .gitignore accordingly.
Signed-off-by: Vincent Stehlé <firstname.lastname@example.org>