added documentation for the new Symfony 2.5 progress bar
feature #3626 added documentation for the new Symfony 2.5 progress bar (fabpot)

This PR was merged into the master branch.

Discussion
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added documentation for the new Symfony 2.5 progress bar

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | yes (symfony/symfony#10356)
| Applies to    | 2.5+
| Fixed tickets | n/a

Commits
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9e2727d added documentation for the new Symfony 2.5 progress bar
Merge remote-tracking branch 'origin/master'