Use the way better Symfony exception dumper.
Merge pull request #1079 from cmfcmf/symfony-exception

Use the way better Symfony exception dumper.
Do not register hooks and eventhandlers twice, closes #727, closes #484.
Do not delete messages if $delete = false.
Merge pull request #1080 from cmfcmf/logutil-fix

Do not delete messages if $delete = false.
Merge pull request #1078 from cmfcmf/#727#484

Do not register hooks and eventhandlers twice, closes #727, closes #484.