Return a list of sqlite databases in the queue_dir

def _list_queues():
    '''
    Return a list of sqlite databases in the queue_dir
    '''
    queue_dir = __opts__['sqlite_queue_dir']
    files = os.path.join(queue_dir, '*.db')
    paths = glob.glob(files)
    queues = [os.path.splitext(os.path.basename(item))[0] for item in paths]

    return queues