Updating Symfony version from 2.4 to 2.5

The descriptions are still displaying the old version
Configuring composer.json to use the 2.5 version

Configuring composer.json to use the 2.5 version Rather than 2.4
minor #4026 Updating Symfony version from 2.4 to 2.5 (danielsan)

This PR was merged into the 2.5 branch.

Discussion
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Updating Symfony version from 2.4 to 2.5

The descriptions are still displaying the old version

Commits
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81d962f Configuring composer.json to use the 2.5 version
2299df0 Updating Symfony version from 2.4 to 2.5