Merge pull request #370 from symfony-fr/2.3

Merge back 2.3 to master
Merge pull request #371 from symfony-fr/2.3

Merge back 2.3 to 2.4
Merge pull request #373 from symfony-fr/2.3

Merging 2.3 into 2.4
Merge pull request #374 from symfony-fr/2.4

Merging 2.4 into master
Quelques erreurs corrigées

Quelques erreurs corrigées
Merge pull request #380 from younesherlock/master

Updated css_selector.rst : fixed an error