This PR was merged into the 1.2 branch.

Discussion
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Improve code coverage of SecurityTrait

Additional tests to cover:
- Empty token: https://github.com/silexphp/Silex/blob/1.2/src/Silex/Application/SecurityTrait.php#L33-35
- Invalid user: https://github.com/silexphp/Silex/blob/1.2/src/Silex/Application/SecurityTrait.php#L37-39

Commits
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95023886 Add tests