Unregister initial loader when using ApcClassLoader
merged branch Seldaek/patch-3 (PR #570)

This PR was merged into the master branch.

Discussion
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Unregister initial loader when using ApcClassLoader

I think it's quite bad to have twice the same loader registered because for autoloading classes (or class_exists calls) not handled by the main symfony/composer loader, it'll be called twice.

Commits
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43b3c14 Unregister initial loader when using ApcClassLoader