Update CHANGELOG.md

Author: photonstorm

CHANGELOG.md

@@ -56,6 +56,7 @@
 * `ArcadePhysics.furthest` will now no longer ever return the source in the target results (thanks @samme)
 * `RequestAnimationFrame.target` is a new property that controls the fps rate (in ms) when setTimeout is used (thanks @pavels)
 * The `WebAudioSoundManager.unlock` method will now listen for `keydown` events in order to unlock the Audio Context, as well as touch and pointer events, making it more accessible (thanks Nick Tipping)
+* The `requestAnimationFrame` polyfill no longer expects a Browserify environment and uses `window` through-out, it also no longer adds in the same as performance.now does.
 
 ### Bug Fixes