修改文档

README.md

@@ -1,3 +1,21 @@
 Fork from [mderrick/react-html5video](https://github.com/mderrick/react-html5video)
 
-Add speed/playbackRate control
+Add speed/playbackRate control
+
+Install dependencies.
+
+```bash
+$ npm install
+```
+
+Start server.
+
+```bash
+$ npm start
+```
+
+Build dist.
+
+```bash
+$ npm run build
+```