refactored session code to make it more reusable
feature #842 [2.0] refactored session code to reuse Symfony listeners (fabpot)

This PR was merged into the 2.0-experimental branch.

Discussion
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[2.0] refactored session code to reuse Symfony listeners

Now that HttpKernel contains Symfony listeners for session, let's use them.

Commits
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7fbae7f refactored session code to make it more reusable