阶段2:拆分为 ES Module + Rollup 构建,重写 README

- src/ 下拆分为入口/语言包/默认配置/主函数/工具模块,主函数整体搬入零改动
- rollup 打包 UMD(moeplayer.js + moeplayer.min.js),用户使用方式不变
- 库拷贝逻辑移至 scripts/copy-libs.js
- README 重写:中文文档、快速开始、路线图、致谢原作者
- index.html 增加皮肤切换演示(默认/红色/西瓜)

index.html

@@ -3,7 +3,7 @@
 	<head>
 		<meta charset="UTF-8">
 		<title>MoePlayer</title>
-		<link type="text/css" rel="stylesheet" href="moeplayer/css/moeplayer.css" />
+		<link id="skin" type="text/css" rel="stylesheet" href="moeplayer/css/moeplayer.css" />
 		<!--
 			如果需要使用其它语言，请在此处引入相应的js,比如:<script type="text/javascript" src="moeplayer/language/en.js" charset="UTF-8"></script>
 		-->
@@ -44,12 +44,22 @@
 			player.ended(function(){
 				document.getElementById('state').innerHTML='监听到播放结束';
 			});
+			//皮肤切换:替换引入的CSS文件
+			function changeSkin(css){
+				document.getElementById('skin').href='moeplayer/css/'+css;
+			}
 		</script>
 		<p>以下链接指向原 ckplayer 项目：</p>
 		<p>官网：<a href="https://www.ckplayer.com" target="_blank">www.ckplayer.com</a></p>
 		<p>手册：<a href="https://www.ckplayer.com/manual/" target="_blank">www.ckplayer.com/manual/</a></p>
 		<p>社区：<a href="https://bbs.ckplayer.com/" target="_blank">bbs.ckplayer.com</a></p>
 		<p>全功能演示：<a href="https://www.ckplayer.com/demo.html" target="_blank">www.ckplayer.com/demo.html</a></p>
+		<p>皮肤切换：</p>
+		<p>
+			<button type="button" onclick="changeSkin('moeplayer.css')">默认</button>
+			<button type="button" onclick="changeSkin('moeplayer.red.css')">红色</button>
+			<button type="button" onclick="changeSkin('moeplayer.ixigua.css')">西瓜</button>
+		</p>
 		<p>控制示例：</p>
 		<p>
 			<button type="button" onclick="player.play()" >播放</button>