go swagger 生成api文档

https://www.cnblogs.com/ezgod/p/14308301.html

go get -u github.com/swaggo/swag/cmd/swag  #这个-u参数会将依赖包下载下来并且将其二进制程序安装在gopath/bin里，这里提前请将此目录加入环境变量，以免在执行swag init -g .\main\main.go时报找不到命令
go get github.com/swaggo/gin-swagger
go get github.com/swaggo/gin-swagger/swaggerFiles