minor #1306 Address bc changes from Symfony 2.8 to Symfony 3 (bestattendance)
minor #1306 Address bc changes from Symfony 2.8 to Symfony 3 (bestattendance)

This PR was merged into the 2.0.x-dev branch.

Discussion
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Address bc changes from Symfony 2.8 to Symfony 3

Ref: https://github.com/silexphp/Silex/issues/1302

How is pre-Symfony3 documentation handled?  Is that a separate page or should notes on pre-Symfony3 usage be included on this page?

Commits
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b29c33f Address bc changes from Symfony 2.8 to Symfony 3

fabpot/Silex,gencer/Silex,fabpot/Silex,romainneutron/Silex,romainneutron/Silex,romainneutron/Silex,silexphp/Silex