执行 truffle unbox pet-shop 报错，因为无法连接raw.githubusercontent.com，需要翻墙或者配置本地host文件

解决方案：

1、通过   https://www.ipaddress.com   查询 raw.githubusercontent.com 的 地址。

2、配置host文件  C:\Windows\System32\drivers\etc\host   增加以下内容

199.232.68.133  raw.githubusercontent.com

√ Preparing to download box
× Downloading
Unbox failed!
RequestError: Error: getaddrinfo ENOENT raw.githubusercontent.com raw.githubusercontent.com:443
    at new RequestError (C:\Program Files\Node\node_modules\truffle\build\webpack:\node_modules\request-promise-core\lib\errors.js:14:1)
    at Request.plumbing.callback (C:\Program Files\Node\node_modules\truffle\build\webpack:\node_modules\request-promise-core\lib\plumbing.js:87:1)
    at Request.RP$callback [as _callback] (C:\Program Files\Node\node_modules\truffle\build\webpack:\node_modules\request-promise-core\lib\plumbing.js:46:1)
    at self.callback (C:\Program Files\Node\node_modules\truffle\build\webpack:\node_modules\request\request.js:185:1)
    at Request.emit (events.js:198:13)
    at Request.onRequestError (C:\Program Files\Node\node_modules\truffle\build\webpack:\node_modules\request\request.js:881:1)
    at ClientRequest.emit (events.js:198:13)
    at TLSSocket.socketErrorListener (_http_client.js:401:9)
    at TLSSocket.emit (events.js:198:13)
    at emitErrorNT (internal/streams/destroy.js:91:8)
    at emitErrorAndCloseNT (internal/streams/destroy.js:59:3)
    at process._tickCallback (internal/process/next_tick.js:63:19)
Truffle v5.1.32 (core: 5.1.32)
Node v10.20.0