Make getNode function public

The getNode function should be public so that DomElement objects can be accessed directly if need be.
[Process] Added ProcessBuilder::addEnvironmentVariables
[Form] Fix of "PATCH'ed forms are never valid"

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8111
| License       | MIT
Return BC compatibility for `@Route` parameters and default values
[Validator] Fixed groups argument misplace for validateValue method from validator class
removed extraneous whitespaces
[FrameworkBundle] The config:dump-reference command shows the list of bundles with the table helper
Fixed NativeSessionStorage:regenerate when does not exists
merged branch lyrixx/fix-8460 (PR #8479)

This PR was submitted for the master branch but it was merged into the 2.2 branch instead (closes #8479).

Discussion
----------

 	[HttpFoundation] Fixed NativeSessionStorage:regenerate when does not exists

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8460
| License       | MIT
| Doc PR        | -

**warning** I did not try to reproduce this bug, so I am not sure it fixes the issue. I just open a PR with the suggested patch. Tests for http foundation are OK. I am not sur it's the best way to fix this issue as I do not understand why symfony reach this code if $_SESSION is not set.

Commits
-------

f5d59fb [HttpFoundation] Fixed NativeSessionStorage:regenerate when  does not exists
updated CHANGELOG for 2.2.4
update CONTRIBUTORS for 2.2.4
updated VERSION for 2.2.4
bumped Symfony version to 2.2.5
fixed typo
[DependencyInjection] Add exception for service name not dumpable in PHP
Merge branch '2.2' into 2.3

* 2.2:
  fixed typo
  bumped Symfony version to 2.2.5
  updated VERSION for 2.2.4
  update CONTRIBUTORS for 2.2.4
  updated CHANGELOG for 2.2.4
  Fixed NativeSessionStorage:regenerate when does not exists
  removed extraneous whitespaces

Conflicts:
	src/Symfony/Component/HttpKernel/Kernel.php
updated CHANGELOG for 2.3.2
updated VERSION for 2.3.2
fix issue #8499 modelChoiceList call getPrimaryKey on a non object
merged branch jaugustin/fix-propel-modelChoiceList (PR #8505)

This PR was merged into the 2.2 branch.

Discussion
----------

[bridge] [propel1] [ModelChoiceList] fix issue #8499 call getPrimaryKey on a non object

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8499
| License       | MIT
| Doc PR        | no

This fix an issue #8499 introduced by the PR #8223

CC @willdurand @havvg

Commits
-------

2ebb783 fix issue #8499 modelChoiceList call getPrimaryKey on a non object