Fixes #5915: Error message when trying to delete a system directive is horrible
Merge pull request #12 from fanf/bug_5915/error_message_when_trying_to_delete_a_system_directive_is_horrible

Fixes #5915: Error message when trying to delete a system directive is h...
Merge branch 'branches/rudder/2.10' into branches/rudder/2.11
Merge branch 'branches/rudder/2.11' into branches/rudder/3.0