List all tokens in the store.

    :param opts: Salt master config options
    :returns: List of dicts (tokens)

def list_tokens(opts):
    '''
    List all tokens in the store.

    :param opts: Salt master config options
    :returns: List of dicts (tokens)
    '''
    ret = []
    for (dirpath, dirnames, filenames) in salt.utils.path.os_walk(opts['token_dir']):
        for token in filenames:
            ret.append(token)
    return ret