Changing uses of we to you in the service container book chapter
Edited JMSSecurityExtraBundle doc link

It now points to the real documentation of this bundle and the version used in Symfony2.0, which is 1.0.
[Dependency Injection] small changes
Created intro text of the Twig Reference
Added functions section
Added filter section
Created tags section
Added 'almost core' bundles
Added missing dot in property path assembly.
Adding link to the Template annotation
Adding link to how to render templates
Adding link to @ParamConverter
Changed uses of we in security cookbooks
Removed space around dot operator.
Updated screenshot and information about changing base branch to 2.0 for pull requests
Fixing bug where Null needs to be escaped in yaml - see symfony/symfony#5364
Typo in filepath (casing) leading to class not found error
Added information about branches, updated tip about merging times
Add paragraph about ask a validated response
Fixed incorrect wording