message: Change mimetype
diff: @@ -58,7 +58,7 @@ export class CourseEditComponent implements OnInit {
  ngOnInit() {
  this.generateForm();
  this.uploader = new FileUploader({
  - allowedMimeType: ['application/vnd.ms-excel'],
  + allowedMimeType: ['text/plain'],
  url: '/api/courses/' + this.id + '/whitelist',
  headers: [{
  name: 'Authorization',
  