[Routing] add support for path-relative and scheme-relative URL generation
[Routing] added tests for generating relative paths and network paths
[Routing] made reference type fully BC and improved phpdoc considerably
fix phpdoc of UrlGeneratorInterface that missed some exceptions and improve language of exception message
[HttpFoundation] Update docblock for non-working method
updated CHANGELOG for 2.0.21
updated VERSION for 2.0.21
bumped Symfony version to 2.0.21-DEV
add preferred_query option to ModelType

This enables the ModelChoiceList to use 'preferred_choices' of the parent ChoiceType.
use preferred_choices in favor of preferred_query
HttpUtils must handle RequestMatcher too
Fixed php doc of GenericEvent::__construct
merged branch lyrixx/fix-eventdispatcher (PR #6487)

This PR was merged into the 2.1 branch.

Commits
-------

abf5e51 [EventDispatcher] Fixed php doc of GenericEvent::__construct

Discussion
----------

[EventDispatcher] Fixed php doc of GenericEvent::__construct

```
Bug fix: yes (doc)
Feature addition: no
Backwards compatibility break: no
Symfony2 tests pass: yes (no modified)
Fixes the following tickets: -
Todo: -
License of the code: MIT
```

---------------------------------------------------------------------------

by drak at 2012-12-26T21:51:54Z

Well spotted.
merged branch havvg/feature/propel1-modelchoice-preferred (PR #6454)

This PR was merged into the 2.1 branch.

Commits
-------

05fca6d use preferred_choices in favor of preferred_query
6855cff add preferred_query option to ModelType

Discussion
----------

[Propel1] add preferred_choices option to ModelType

This enables the ModelChoiceList to use 'preferred_choices' of the parent ChoiceType.

Ping @willdurand

---------------------------------------------------------------------------

by willdurand at 2012-12-22T09:39:39Z

:+1:
[Tests] Fix namespaces
merged branch franmomu/fix_test_namespaces (PR #6497)

This PR was merged into the 2.1 branch.

Commits
-------

a6704f3 [Tests] Fix namespaces

Discussion
----------

[Tests] Fix namespaces
[Form] Fixed test regression introduced in #6440
merged branch bschussek/issue6440 (PR #6505)

This PR was merged into the 2.1 branch.

Commits
-------

87dcf25 [Form] Fixed test regression introduced in #6440

Discussion
----------

[Form] Fixed test regression introduced in #6440

Bug fix: yes
Feature addition: no
Backwards compatibility break: no
Symfony2 tests pass: yes
Fixes the following tickets: -
Todo: -
License of the code: MIT
Documentation PR: -
Revert "merged branch ricardclau/rename_choice_to_oneof (PR #6360)"

This reverts commit 1de60c902c66c01c9c8c24935cd9efe90b6333e5, reversing
changes made to e3cc337b000dc4049e0e0ddb985d26ddb4abcd08.

Conflicts:
	UPGRADE-2.2.md
Improve timing safe comparison function

Improve the timing safe comparison function to better handle cases where input is of different length.

Note that it is now important to always pass any string that the user can directly control to the second parameter of the function. Otherwise, length information may be leaked.