解决413 Request Entity Too Large nginx/1.14.0
解决方法：
nginx的error.log的错误日志：
2018/10/17 16:31:45 [error] 23693#0: *76448222 client intended to send too large body: 1329896 bytes, client: 192.168.1.101, server: , request: "POST /shortMessage HTTP/1.1", host: "192.168.1.113:8500"
其中1329896 bytes是1.2M，也就是说请求的数据达到了1.2M，超过了nginx的默认上传文件大小限制，默认1M.