[Filesystem] Added few new behaviors:

 - add a IOException and a main filesystem exception interface
 - whenever an action fails, an IOException is thrown
 - add access to the second and third arguments of touch() function
 - add a recursive option for chmod()
 - add a chown() method
 - add a chgrp() method
 - Switch the 'unlink' global function in Filesystem::symlink to Filesystem::remove.

BC break: mkdir() function now throws exception in case of failure instead of returning Boolean value.
Add Changelog BC Break note
[FileSystem] explains possible failure of symlink creation in windows
Merge pull request #1 from SamsonIT/FilesystemExceptions

[FileSystem] explain possible failure of symlink creation in windows
merged branch romainneutron/FilesystemExceptions (PR #4330)

Commits
-------

a20fc68 Merge pull request #1 from SamsonIT/FilesystemExceptions
8eca661 [FileSystem] explains possible failure of symlink creation in windows
b1f8744 Add Changelog BC Break note
24eb396 [Filesystem] Added few new behaviors:

Discussion
----------

[Filesystem] Consistence and enhancements for Filesystem

Bug fix: no
Feature addition: yes
Backwards compatibility break: **yes**
Symfony2 tests pass: yes
Fixes the following tickets: None
License of the code: MIT

This PR adds features and introduce a backward compatibility break.

features :
- whenever an action fails, a \RuntimeException is thrown
- add access to the second and third arguments of ``touch`` function
- add a recursive option for chmod
- add a chown method
- add a chgrp method

The backward compatibility break happens in the mkdir method : Before this PR, a boolean is returned ; true if all directories were created, false otherwise.
It now returns nothing.

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by travisbot at 2012-05-18T14:26:42Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1367000) (merged 83cdd622 into 1e15f210).

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by fabpot at 2012-05-20T02:40:28Z

To be consistent, we should throw exception whenever some operation fails.

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by romainneutron at 2012-05-20T21:10:23Z

I fix the consistency ; mkdir now throws an exception if a directory creation fails.
This introduce a BC break, see PR message which has been updated with all features and BC break.

Added chgrp and chown methods
Add options for touch
Add recursive option for chmod

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by travisbot at 2012-05-20T21:11:47Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1383619) (merged a4d1eeb8 into 1407f112).

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by travisbot at 2012-05-22T10:49:06Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1399027) (merged 7e14b6bd into 517ae43f).

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by travisbot at 2012-05-22T10:58:10Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1399083) (merged 71852653 into 517ae43f).

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by travisbot at 2012-05-22T11:18:44Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1399194) (merged 7645bad3 into 517ae43f).

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by travisbot at 2012-05-23T18:21:47Z

This pull request [fails](http://travis-ci.org/symfony/symfony/builds/1414091) (merged b049d5b1 into 517ae43f).

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by travisbot at 2012-05-23T18:26:19Z

This pull request [fails](http://travis-ci.org/symfony/symfony/builds/1414123) (merged 34903466 into 517ae43f).

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by travisbot at 2012-05-29T16:07:26Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1467173) (merged b1d1eb2e into adf07f1e).

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by travisbot at 2012-05-29T16:19:38Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1467261) (merged 42015ffa into adf07f1e).

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by romainneutron at 2012-06-01T14:30:45Z

Any news about this PR ?

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by stloyd at 2012-06-08T09:57:39Z

@romainneutron You need to [squash](http://www.silverwareconsulting.com/index.cfm/2010/6/6/Using-Git-Rebase-to-Squash-Commits) your commits, and add more proper message in squashed commit i.e.:

> [Filesystem]  Added few new behaviors:
* whenever an action fails, a `RuntimeException` is thrown
* add access to the second and third arguments of `touch()` function
* add a recursive option for `chmod()`
* add a `chown()` method
* add a `chgrp()` method

> BC break: `mkdir()` function throw exception in case of failture instead of returning Boolean value.

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by romainneutron at 2012-06-08T10:59:55Z

@stloyd squash done !

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by travisbot at 2012-06-08T11:26:20Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1565540) (merged 8f55ddb6 into f8e68e58).

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by travisbot at 2012-06-08T11:41:45Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1566247) (merged 880312b6 into f8e68e58).

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by romainneutron at 2012-06-09T11:42:24Z

I've added documentation to the Filesystem component : https://github.com/symfony/symfony-docs/pull/1439

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by travisbot at 2012-06-09T16:47:20Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1577754) (merged 5647ad41 into f8a09db5).

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by stloyd at 2012-06-13T14:47:31Z

@romainneutron You probably need to rebase your code as some changes were merge into master for `Filesystem`.

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by romainneutron at 2012-06-13T15:17:31Z

@stloyd rebase OK !

by the way, do you have any idea when/if this PR will be merged ?

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by travisbot at 2012-06-13T15:20:44Z

This pull request [passes](http://travis-ci.org/symfony/symfony/builds/1611591) (merged c8b86c68 into c07e9163).

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by fabpot at 2012-06-16T16:40:50Z

You need to add a note about the BC breaks in the CHANGELOG file.

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by fabpot at 2012-06-16T16:43:20Z

Also, instead of using `\RuntimeException`, I would create a custom exception like we have done in other components (an interface + a RuntimeException that implements the interface and extends \RuntimeException). The exception name can be something like `IOException`.

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by travisbot at 2012-06-18T10:11:20Z

This pull request [fails](http://travis-ci.org/symfony/symfony/builds/1645757) (merged 925a8234 into 0b8b76bf).

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by stloyd at 2012-06-18T10:14:52Z

@fabpot Anything blocking merge of this PR ? (tests are failing because of issue in master, not releted to this PR)

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by romainneutron at 2012-06-18T10:29:20Z

@fabpot @stloyd the latest push was just a rebase push for PR 4577 (https://github.com/symfony/symfony/issues/4577)
I'm currently fixing the Exception and changelog things, I'll push very soon

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by romainneutron at 2012-06-18T10:44:38Z

@fabpot I've added the exception and the exception interface, add the changelog info

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by travisbot at 2012-06-18T10:53:34Z

This pull request [fails](http://travis-ci.org/symfony/symfony/builds/1645981) (merged 634d6fb9 into 0b8b76bf).

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by romainneutron at 2012-06-18T11:08:43Z

As reported by @stloyd the PR is failing due to an issue in the master, I re-push and trig the PR build when this issue is solved

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by travisbot at 2012-06-18T11:16:58Z

This pull request [fails](http://travis-ci.org/symfony/symfony/builds/1646006) (merged 2f65945a into 0b8b76bf).