Add command to make symfony.phar executable.
bug #4533 Add command to make symfony.phar executable. (xelaris)

This PR was submitted for the 2.7 branch but it was merged into the 2.3 branch instead (closes #4533).

Discussion
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Add command to make symfony.phar executable.

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

Commits
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dd9de4e Add command to make symfony.phar executable.