Removed Batoto-specific features from Manager.
Manager now only detects whether the URL has a scraper class and will import the class and initialize an object with the URL if it does. Batoto class now has a variable for the URL it was initialized and detects if it was initialized with a chapter or not and will set variable init_with_chapter True/False based on that. If the object was intialized with a chapter URL, Batoto.series_chapters() will only return the chapter it was initialized with, unless Batoto.series_chapters() is called with all_chapters=True. Previous 'all_chapters' has been renamed 'all_versions', which corresponds to its functionality better.