drop Symfony 2.2 support

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | yes (bumped dependency)
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | https://github.com/symfony-cmf/symfony-cmf-docs/pull/449


Get rid of the cmf_request_aware tag in bundles

* [x] RoutingBundle/Resources/config/routing-dynamic.xml
* [x] SimpleCmsBundle/Resources/config/menu-phpcr.xml
* [x] MenuBundle/Resources/config/persistence-phpcr.xml
* [x] MenuBundle/Resources/config/voters.xml
* [x] MediaBundle/Resources/config/persistence-phpcr-event-imagine.xml
* [x] BlockBundle/Resources/config/services.xml
* [x] BlockBundle/Resources/config/persistence-phpcr.xml
* [x] check whether we inject the container in other places.