update README: Let me know

README.md

@@ -14,6 +14,8 @@
 
 [Demo](http://dplayer.js.org/)
 
+Using APlayer on your project? [Let me know!](https://github.com/DIYgod/DPlayer/issues/31)
+
 Screenshot
 ![image](http://i.imgur.com/207ch36.jpg)