update symfony dependency
update symfony dependency

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