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__Tasks:__

- [x] test coverage
- [ ] gather feedback for my changes

__Informations:__

| Q             | A
| ------------- | ---
| Tests pass?   | yes
| Fixed tickets | part of https://github.com/sulu-cmf/sulu-standard/issues/125
| BC Breaks     | none
| Doc           | none
Use `$e` as the exception variable. This is consistent with 90% of Symfony code, and it is inconsistent in the Sulu code base (e.g. `$e`, `$ex`, $exc`)