Upgrade Symfony to 3.2.x

Today I stucked on this exception:
Error: Call to undefined method AppKernel::setAnnotatedClassCache()

after I upgraded from 3.1 to 3.2.1.

The cause was an old app/boostrap.php.cache.

Just delete the file and regenerate it with the following command:


 php vendor/sensio/distribution-bundle/Sensio/Bundle/DistributionBundle/Resources/bin/build_bootstrap.php