updated composer.json to accept Symfony 2.2.*
updated composer.json to accept Symfony 2.2.*

This was the only bundle that was not up to date for the Symfony SE version 2.2.
taueres/AsseticBundle,webmozart/AsseticBundle,jandevani/AsseticBundle,symfony/AsseticBundle,ThatCheck/AsseticBundle,Soullivaneuh/AsseticBundle,robertfausk/AsseticBundle,artursvonda/AsseticBundle,xabbuh/AsseticBundle,symfony/AsseticBundle,nexylan/AsseticBundle,javiereguiluz/assetic-bundle,Soullivaneuh/AsseticBundle,xabbuh/AsseticBundle,artursvonda/AsseticBundle,robertfausk/AsseticBundle,robertfausk/AsseticBundle,ThatCheck/AsseticBundle,webmozart/AsseticBundle,taueres/AsseticBundle,stof/AsseticBundle,peterkokot/AsseticBundle,javiereguiluz/assetic-bundle,nexylan/AsseticBundle,Soullivaneuh/AsseticBundle,stof/AsseticBundle,shieldo/AsseticBundle,peterkokot/AsseticBundle,shieldo/AsseticBundle,symfony/assetic-bundle,symfony/AsseticBundle,symfony/assetic-bundle,stof/AsseticBundle,symfony/assetic-bundle,shieldo/AsseticBundle,jandevani/AsseticBundle,nexylan/AsseticBundle,artursvonda/AsseticBundle,javiereguiluz/assetic-bundle,taueres/AsseticBundle,ThatCheck/AsseticBundle,jandevani/AsseticBundle