Resolve "Unbegrenzte Veranstaltungen haben Startzeitpunkt!"

app/controllers/admin/courseplanning.php

app/controllers/admin/user.php

app/controllers/admission/restricted_courses.php

app/controllers/blubber.php

app/controllers/course/timesrooms.php

app/controllers/course/topics.php

app/controllers/file.php

app/controllers/news.php

app/controllers/questionnaire.php

app/controllers/shared/modul.php

app/routes/Course.php

app/views/file/choose_file_from_course.php

app/views/file/choose_folder_from_course.php

lib/classes/AdminCourseFilter.class.php

lib/classes/MyRealmModel.php

lib/classes/coursewizardsteps/BasicDataWizardStep.php

lib/classes/searchtypes/StandardSearch.class.php

lib/models/Course.class.php

lib/models/Semester.class.php