Update dead demo URL

Update dead demo URL for game "clumsy-bird" to a working demo URL.

README.md

@@ -752,7 +752,7 @@ _Command-line file upload_
 - [A Dark Room](https://github.com/doublespeakgames/adarkroom) - Minimalist text adventure game for your browser. ([Demo](http://adarkroom.doublespeakgames.com/)) `MPL-2.0` `HTML5`
 - [Agar.IO Clone](https://github.com/huytd/agar.io-clone) - Agar.io clone written with Socket.IO and HTML5 canvas. `MIT` `Nodejs`
 - [battlecraft](https://github.com/jbreindel/battlecraft) - Fully distributed multiplayer browser game. ([Demo](http://battlecraft.online)) `Apache-2.0` `Erlang`
-- [Clumsy Bird](https://github.com/ellisonleao/clumsy-bird) - MelonJS port of the famous Flappy Bird Game. ([Demo](http://www.ellison.rocks/clumsy-bird/)) `MIT` `Nodejs`
+- [Clumsy Bird](https://github.com/ellisonleao/clumsy-bird) - MelonJS port of the famous Flappy Bird Game. ([Demo](http://ellisonleao.github.io/clumsy-bird/)) `MIT` `Nodejs`
 - [elevatorsaga](http://play.elevatorsaga.com/) - The elevator programming game. ([Source Code](https://github.com/magwo/elevatorsaga)) `MIT` `Javascript`
 - [Hextris](https://github.com/Hextris/hextris) - Fast paced HTML5 puzzle game inspired by Tetris. ([Demo](http://hextris.io/)) `GPL-3.0` `HTML5`
 - [Lila](https://lichess.org/) - The forever free, adless and open source chess server powering lichess.org, with official iOS and Android client apps. ([Source Code](https://github.com/ornicar/lila)) `AGPL-3.0` `Scala`