位置：config/config.php
增加行：
‘proxy‘ => ‘<ip>:<port>‘,如果有啥不明白的，可以看config.sample.php，里面有这段：
/**
* The URL of your proxy server, for example ``proxy.example.com:8081``.
*
* Defaults to ``‘‘`` (empty string)
*/
‘proxy‘ => ‘‘,
/**
* The optional authentication for the proxy to use to connect to the internet.
* The format is: ``username:password``.
*
* Defaults to ``‘‘`` (empty string)
*/
‘proxyuserpwd‘ => ‘‘,