message: API: Adjust some FixtureUtils *Model return types
diff: import {User} from '../src/models/User';
  import {Course, ICourseModel} from '../src/models/Course';
  import {IUserModel} from '../src/models/User';
  -import {Lecture} from '../src/models/Lecture';
  +import {Lecture, ILectureModel} from '../src/models/Lecture';
  import {Unit, IUnitModel} from '../src/models/units/Unit';
  import {ICourse} from '../../shared/models/ICourse';
  import {ILecture} from '../../shared/models/ILecture';
  @@ -117,17 +117,17 @@ export class FixtureUtils {
  return this.getRandom<ICourse>(coursesWithAllUnitTypes, hash);
  }
  - public static async getCourseFromLecture(lecture: ILecture): Promise<ICourse> {
  + public static async getCourseFromLecture(lecture: ILecture): Promise<ICourseModel> {
  return Course.findOne({lectures: { $in: [ lecture._id ] }});
  }
  - public static async getCourseFromUnit(unit: IUnit): Promise<ICourse> {
  + public static async getCourseFromUnit(unit: IUnit): Promise<ICourseModel> {
  return Course.findById(unit._course);
  }
  - public static async getRandomLecture(hash?: string): Promise<ILecture> {
  + public static async getRandomLecture(hash?: string): Promise<ILectureModel> {
  const array = await this.getLectures();
  - return this.getRandom<ILecture>(array, hash);
  + return this.getRandom<ILectureModel>(array, hash);
  }
  public static async getRandomLectureFromCourse(course: ICourse, hash?: string): Promise<ILecture> {
  @@ -189,7 +189,7 @@ export class FixtureUtils {
  .populate('whitelist');
  }
  - public static async getLectures(): Promise<ILecture[]> {
  + public static async getLectures(): Promise<ILectureModel[]> {
  return Lecture.find();
  }
  