* [update] parser/baidu
  - support AQI info, add three data types, AQI, AQID, AQIT
  - change the default argument to '天气'
* [update] all parser, add homepage in help message
* [update] parser/google-hk, change the default argument to '天氣'
* [update] set the default parser to google-hk, for the goole parser not works well now