Docs update.

Author: photonstorm

README.md

@@ -253,6 +253,7 @@ Version 2.4 - "Katar" - in dev
 * Phaser.StateManager would incorrectly call `loadUpdate` and `loadRender` while the game was paused or if the State didn't have an `update` or `render` method defined, even after the loader was completed. Although this is a bug fix it's still an API change should you have been using the `loadUpdate/Render` calls in the old way. Also the StateManager no longer calls `preRender` unless the State `create` method has *finished*. If the State doesn't have a `create` method then `preRender` runs immediately.
 * Frame.uuid has been removed (was flagged as deprecated for several releases). This has a two-fold effect: First it means that the property no longer exists and secondly it means that the AnimationParser (the class responsible for loading sprite sheets and texture atlases) no longer has to call either RandomDataGenerator.uuid OR populates the PIXI.TextureCache. The first saves some CPU time and the second saves memory by not creating references to textures it doesn't ever use. The PIXI.TextureCache is now ignored by Phaser other than for the `__missing` and `__default` textures.
 * Phaser.AnimationParser methods `JSONData`, `JSONDataHash` and `XMLData` have all had their `cacheKey` parameter removed as it's no longer used.
+* Input.deleteMoveCallback no longer takes an integer as its parameter. Now you have to give it the original callback and context in order to remove it. This is to protect against index invalidation (see the fixed Bugs list)
 
 ### New Features
 
@@ -346,6 +347,7 @@ Version 2.4 - "Katar" - in dev
 * The SoundManager didn't accurately detect devices or browser environments with no sound card present and would try to carry on using a null Web Audio context (thanks @englercj #1746)
 * The Tween.onStart signal wasn't dispatched if the Tween had a delay set. It's now dispatched immediately if no delay, or after the delay if set. It also respects the `autoStart` parameter and will still dispatch even if `autoStart` is true.
 * PIXI.CanvasTinter.tintWithMultiply was performing a double drawImage operation for no reason. Simplified down to a single drawImage call.
+* Input.addMoveCallback used to return the index of the callback entry in the internal `moveCallbacks` array. However as callbacks were removed the indexes became invalid, potentially causing a future `Input.deleteMoveCallback` to remove the wrong callback entirely or error. Input.deleteMoveCallback now takes the original callback and context as its parameters to ensure deletion safety.
 
 For changes in previous releases please see the extensive [Version History](https://github.com/photonstorm/phaser/blob/master/CHANGELOG.md).