message: Adjust addFileToAssignment's
  Remove "@apiParam currentUser" & add type info.
diff: @@ -305,9 +305,8 @@ export class UnitController {
  * Is called when the user wants to add a file to the assignment.
  * The user can add as much file as she wants as long as the assignment is not finalized/submitted yet.
  *
  - * @apiParam unitId
  - * @apiParam uploadedFile
  - * @apiParam currentUser
  + * @apiParam {String} unitId
  + * @apiParam {Object} uploadedFile
  *
  * @apiError NotFoundError The unit was not found or there isn't an assignment from the current user in the unit.
  */
  