minor #513 Remove part related to Assetic which is no longer used (apetitpa)
minor #513 Remove part related to Assetic which is no longer used (apetitpa)

This PR was merged into the master branch.

Discussion
----------

Remove part related to Assetic which is no longer used

Since #387 Assetic is no longer used to manage assets.

Commits
-------

f9411dc Remove part related to Assetic which is no longer used

yodur2potassium/test-behat-selenium-symfo,javiereguiluz/symfony-demo,voronkovich/symfony-demo,javiereguiluz/symfony-demo,yceruto/symfony-demo,yodur2potassium/test-behat-selenium-symfo,dzuelke/symfony-demo,TomasVotruba/symfony-demo,dzuelke/symfony-demo,nilamkhedkar1/symfony_demo,Codeception/symfony-demo,nilamkhedkar1/symfony_demo,symfony/symfony-demo,nilamkhedkar1/symfony_demo,javiereguiluz/symfony-demo,Codeception/symfony-demo,voronkovich/symfony-demo,yodur2potassium/test-behat-selenium-symfo,bocharsky-bw/symfony-demo,yceruto/symfony-demo,TomasVotruba/symfony-demo,Codeception/symfony-demo,voronkovich/symfony-demo,symfony/symfony-demo,bocharsky-bw/symfony-demo,bocharsky-bw/symfony-demo,yceruto/symfony-demo,dzuelke/symfony-demo,symfony/symfony-demo,TomasVotruba/symfony-demo