Merge pull request #206 from dvirberlo/patch-1

doc(README.md): fix online demo link

Author: qiao

README.md

@@ -13,7 +13,7 @@ Introduction
 
 The aim of this project is to provide a path-finding library that can be easily incorporated into web games. It may run on Node.js or the browser.
 
-It comes along with an [online demo](http://qiao.github.com/PathFinding.js/visual) to show how the algorithms execute. (The pathfinding speed is slowed down in the demo)
+It comes along with an [online demo](http://qiao.github.io/PathFinding.js/visual) to show how the algorithms execute. (The pathfinding speed is slowed down in the demo)
 
 Note that this project only provides path-finding algorithms for 2D space. If you need to work in a 3D environment, then you may use [@schteppe](https://github.com/schteppe)'s [fork](https://github.com/schteppe/PathFinding3D.js).