Update Rakefile

Post task with paramter (title, tags, author)
Merge branch 'master' of https://github.com/Treeptik/blog.treeptik.fr
Publishing 'vagrant-la-virtualisation-pour-les-dev'
Merge branch 'master' of https://github.com/Treeptik/blog.treeptik.fr
Ajout du lien twitter
Suppression de l article Log DAO en double