Removes all img_id's files.

def remove_all_files_of_img_id(img_id):
    """
    Removes all img_id's files.
    """
    files = get_files_by_img_id(img_id, check_hash=False)
    if files:
        os.remove(media_path(files['main']))
        for fn in files['variants'].values():
            os.remove(media_path(fn))