Typo

Author: photonstorm

src/scene/Systems.js

@@ -480,8 +480,8 @@ var Systems = new Class({
     /**
      * Send this Scene to sleep.
      *
-     * A sleeping Scene doesn't run it's update step or render anything, but it also isn't shut down
-     * or have any of its systems or children removed, meaning it can be re-activated at any point and
+     * A sleeping Scene doesn't run its update step or render anything, but it also isn't shut down
+     * or has any of its systems or children removed, meaning it can be re-activated at any point and
      * will carry on from where it left off. It also keeps everything in memory and events and callbacks
      * from other Scenes may still invoke changes within it, so be careful what is left active.
      *