记录一下图片缩放 和截图发送！
图片缩放 https://yihui.name/cn/2007/09/highslide-and-lightbox/ http://www.zhangxinxu.com/jq/balupton_zh/demo/ http://www.dowebok.com/demo/214/ http://www.lanrentuku.com/js/tupian-933.html
截图发送 http://www.ghugo.com/clipboard-api-and-events/ http://jsfiddle.net/baofen14787/8yxc5/ 从剪贴板上传图片文件 https://www.oschina.net/code/snippet_1000238_44042
