add javascript challenge

content/Etudiants/zz2-f5-websec.md

content/slides/1337/bruteforce.html

content/slides/1337/captcha.html

content/slides/1337/csp.html

content/slides/1337/js.html

content/slides/1337/md/browser.md

content/slides/1337/md/bruteforce.md

content/slides/1337/md/captcha.md

content/slides/1337/md/csp.md

content/slides/1337/md/drupalgeddon.md

content/slides/1337/md/heartbleed.md

content/slides/1337/md/js.md

content/slides/1337/md/session.md

content/slides/1337/md/sop.md

content/slides/1337/session.html

content/slides/1337/sop.html

content/slides/main.css

notes.md