unify class definition in relations of simpleormap models, fixes #979

lib/models/Abschluss.php

lib/models/AbschlussKategorie.php

lib/models/AbschlussZuord.php

lib/models/AdmissionApplication.class.php

lib/models/ArchivedCourseMember.class.php

lib/models/Aufbaustudiengang.php

lib/models/AuthUserMd5.class.php

lib/models/AuxLockRule.php

lib/models/BlubberStatusgruppeThread.php

lib/models/CalendarEvent.class.php

lib/models/CalendarUser.class.php

lib/models/Clipboard.class.php

lib/models/ClipboardItem.class.php

lib/models/ColourValue.class.php

lib/models/Contact.class.php

lib/models/Course.class.php

lib/models/CourseDate.class.php

lib/models/CourseEvent.class.php

lib/models/CourseExDate.class.php

lib/models/CourseMarkedEvent.class.php