Removed 2.2 references as it reached eom
Merge branch 'master' into eom-2-2

Conflicts:
	book/security.rst
	components/property_access/introduction.rst
	components/stopwatch.rst
	cookbook/templating/namespaced_paths.rst
	reference/twig_reference.rst
[Security][Acl] Documentation for the new updateUserSecurityIdentity method in Dbal\MutableAclProvider
[Form] added multiple option to file type doc
fixed spaces
Merge branch '2.4'

Conflicts:
	reference/dic_tags.rst
Merge pull request #3319 from lemoinem/features/acl-update-security-id

[WCM][Security][Acl] Documentation for the new updateUserSecurityIdentity method in Dbal\MutableAclProvider
[#3319] Linking to the whole method
Merge branch '2.4'

Conflicts:
	cookbook/form/dynamic_form_modification.rst
[#3319] Fixing typos thanks to @xabbuh
Merge branch '2.4'
Merge pull request #3354 from bamarni/patch-6

[Form] added multiple option to file type doc
Merge branch '2.4'
Merge branch '2.4'

* 2.4:
  use html+jinja instead of html+twig
Merge branch '2.4'
Revert "[#3338] Removing delete_empty details because this is first being committed to 2.3"

This re-introduces the delete_empty documentation to the master (2.5) branch, since it should live there.

This reverts commit 72fa7b4767b5b86053ca92f4052de2dc7c2dac09.
[#3338] Adding versionadded
Merge branch '2.4'
[#3276] Trying to further clarify the session storage directory details
improve the serialization of custom user models

(cherry picked from commit 7b34eabe4b506c3e49e4dedbefee66c1612bb83d)