Move debug command to the debug namespace
feature #4210 Move debug commands to debug namespace (matthieuauger)

This PR was merged into the master branch.

Discussion
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Move debug commands to debug namespace

Related to https://github.com/symfony/symfony/pull/11627

Should we specify that it has been added in 2.6 and that backward compatibility is ensured ?

Commits
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d6dd540 Move debug command to the debug namespace