drop config option for disabling the ckeditor, fixes #3227

app/controllers/course/forum/index.php

app/controllers/messages.php

app/controllers/settings/general.php

app/views/admin/accessibility_info_text/index.php

app/views/course/feedback/_new_edit_feedback_form.php

app/views/course/forum/index/_new_entry.php

app/views/course/forum/index/_post.php

app/views/course/forum/index/_preview.php

app/views/course/lti/edit.php

app/views/course/scm/edit.php

app/views/course/topics/edit.php

app/views/fachabschluss/abschluesse/abschluss.php

app/views/fachabschluss/faecher/fach.php

app/views/fachabschluss/kategorien/kategorie.php

app/views/file/suggest_oer.php

app/views/lvgruppen/lvgruppen/lvgruppe.php

app/views/messages/write.php

app/views/module/module/lvgruppe.php

app/views/module/module/modul.php

app/views/module/module/modulteil.php