[TASK] Some code cleanup

Classes/Controller/AbstractController.php

Classes/Controller/LatestController.php

Classes/Controller/ListByCategoryController.php

Classes/Controller/NewsFeedController.php

Classes/Controller/OverviewController.php

Classes/Controller/PageBrowserController.php

Classes/Controller/SingleViewController.php

Classes/Domain/Model/Category.php

Classes/Domain/Model/CategoryAndNews.php

Classes/Domain/Model/News.php

Classes/Domain/Repository/AbstractRepository.php

Classes/Domain/Repository/CategoryRepository.php

Classes/Domain/Repository/NewsRepository.php

Classes/Service/ImageService.php

Classes/TCA/TcaProvider.php

Classes/UserFunction/AddAdditionalMailRecipients.php

Classes/ViewHelpers/ExtendedIfViewHelper.php

Classes/ViewHelpers/GetReadingTimeViewHelper.php

Classes/ViewHelpers/PageBrowserViewHelper.php

Classes/Xclass/PageRenderer.php