Documentation for debug:event-dispatcher command
feature #4319 Documentation for debug:event-dispatcher command (matthieuauger)

This PR was merged into the master branch.

Discussion
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Documentation for debug:event-dispatcher command

See https://github.com/symfony/symfony-docs/issues/4230

As my english is far from perfect, I tried to make it short. Any feedback/suggestions welcome

Commits
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a4fed11 Documentation for debug:event-dispatcher command