ajaxupload使用说明:
http://blog.csdn.net/teresa502/article/details/7952486
servlet ajaxupload demo:
http://www.cppblog.com/biao/archive/2010/08/13/123375.html
http://luanxiyuan.iteye.com/blog/2095541
ajaxupload异步上传文件
原文：http://www.cnblogs.com/wrencai/p/4612071.html
