Yields sorted (command name, command summary) tuples.

def get_summaries(ordered=True):
    """Yields sorted (command name, command summary) tuples."""

    if ordered:
        cmditems = _sort_commands(commands_dict, commands_order)
    else:
        cmditems = commands_dict.items()

    for name, command_class in cmditems:
        yield (name, command_class.summary)