Add Weather Support Module

Hi wong2:
    I add weather support module to xiaohuangji,  have not change your main py script;
    
    detail intro:
        weather.py:   request weather by city id from http://www.weather.com.cn
        wr.py:  accept city name,  get city id, and import weather.py to get weather
        cityid:   city name and city id, use pickle to dump and load

                                                                                                                                            From huangyuan,  ahaha