Add the Symfony CSSSelector dependency to match the example usage
Add the Symfony CSSSelector dependency to match the example usage

naderman/Silex,arduanov/Silex,romainneutron/Silex,Xephi/Silex,JPry/Silex,mTorres/Silex,mathroc/Silex,SanderKnape/Silex,mathroc/Silex,fhinkel/Silex,CarsonF/Silex,silexphp/Silex,romainneutron/Silex,gencer/Silex,fhinkel/Silex,jdreesen/Silex,lokhman/Silex,mmauri04/Silex,akucherevskiy/developex_test,beealone/Silex,mTorres/Silex,fabpot/Silex,cgsmith/Silex,romainneutron/Silex,naderman/Silex,tcx1000/Silex,SanderKnape/Silex,cgsmith/Silex,Incognito/silex-fork,SpacePossum/Silex,Xephi/Silex,tcx1000/Silex,SpacePossum/Silex,plotek/Silex,mmauri04/Silex,jdreesen/Silex,fabpot/Silex,Incognito/silex-fork,arduanov/Silex,RayRutjes/Silex,naderman/Silex,plotek/Silex,cesarmarinhorj/Silex,akucherevskiy/developex_test,JPry/Silex,akucherevskiy/developex_test,CarsonF/Silex,CarsonF/Silex,cesarmarinhorj/Silex,lokhman/Silex,RayRutjes/Silex,beealone/Silex