Fastdfs与nginx进行压缩图片比率

      参考：http://www.v2ex.com/t/113845

       http://blog.sina.com.cn/openresty

       http://write.blog.csdn.net/postedit

        https://github.com/azurewang/lua-resty-fastdfs/blob/master/lib/resty/fastdfs/storage.lua

//www.jb51.net/sys/CentOS/55070.htm

http://wiki.nginx.org/HttpLuaModule