adding gitlab-ci jobs to do magic on the web

this MR should add the CI job to sync the webpage on the web

if you want to use it you need to setup 4 variables in your gitlab > settings > variables

WEBDAV_URL=https://www.autistici.org/dav/es_hackmeeting
WEBDAV_USERNAME=es_hackmeeting
WEBDAV_REMOTE_PATH=html-es.hackmeeting.org
WEBDAV_PASSWORD=(ask me for it via PM)