Tilemaps in WebGL wouldn't update after the first frame due to a subtle change in how Pixi uploads new textures to the GPU.
TilemapLayer / Tileset performance and documentation

TilemapLayer
 - Added "delta scroll rendering"
   - Enabled (by default) via `renderSettings.enableScrollDelta`
   - Dramatic CPU reduction: 30% to 2% scrolling 50x37 region
   - Side-effect: fixed some Chrome de-opt issues with `render`
   - Various rendering updates and removal of many `_mc` field
 - Made `index` a read-only propert that reflects the layer.index
 - Creates a local cache from tile index -> tileset, added `resetTilesetCache`
   - Also prevents crash when an index not associated with a tileset is
     used; see `missingImageOverfill`.
 - Various debug options moved to `debugSettings` and simplified; documentation updated.
   - Uses `debugSettings.missingImageOverfill` and `tileColor` (deprecated) to display invalid tileset images
 - Only change the context alpha when the tile alpha changes; in Chrome 38
   this removed a .5% penalty
 - Added `renderSettings` which controls misc. rendering/optimizations.
 - Updated documentation to @member, clarified

Tileset
 - Added `containsTileIndex` method to allow being queried if the specific tile index is handled/supported.
 - Uses a firstgid bias and interlacing to fit the data in single densely packed array.
 - Updated documentation to @member, clarified
Merge branch 'dev' of https://github.com/photonstorm/phaser into wip-tilelayer
TilemapLayer / Tileset

- Minor regression fix, increasing argument specifity/documentation
API / documentation consistency updates

- The `disabled` property of various input classes has been inverted to `enabled`.
  Direct/internal usage of `disabled` has been transformed to `!enabled`.
- A `disabled` get/set property has been added to wrap `enabled`, and marked as @deprecated
  This ensures current API compatibility.
Repackaging for 2.1.4 release.
Cache.getRenderTexture will retrieve a RenderTexture that is stored in the Phaser Cache. This method replaces Cache.getTexture which is now deprecated.

Cache.autoResolveURL is a new boolean (default `false`) that automatically builds a cached map of all loaded assets vs. their absolute URLs, for use with Cache.getURL and Cache.checkURL. Note that in 2.1.3 and earlier this was enabled by default, but has since been moved behind this property which needs to be set to `true` *before* you load any assets to enable.

Cache._resolveUrl has been renamed to Cache._resolveURL internally and gained a new parameter. This method is a private internal one.

Cache.getUrl is deprecated. The same method is now available as Cache.getURL.

XML files weren't being added to the URL map.

Cache._resolveURL was causing a Sound double-load in Firefox and causing errors (thanks @domonyiv #1253)
Loader.useXDomainRequest used to be enabled automatically for IE9 but is now always set to `false`. Please enable it only if you know your server set-up / CDN requires it, as some most certainly do, but we're finding them to be less and less used these days, so we feel it's safe to now disable this by default (#1248)

Loader.json was using the wrong context in IE9 with XDomainRequest calls (thanks @pnstickne #1258)
Game.destroy now destroys either the WebGLRenderer or CanvasRenderer, whichever Pixi was using.
Particle.Emitter will now automatically set `particle.body.skipQuadTree` to `true` to help with collision speeds within Arcade Physics.

Particle.Emitter.explode (or `Emitter.start` with the `explode` parameter set to `true`) will immediately emit the required quantity of particles and not delay until the next frame to do so. This means you can re-use a single emitter across multiple places in your game that require explode-style emissions, just by adjusting the `emitter.x` and `emitter.y` properties before calling explode (thanks Insanehero)
New build files for testing.
Tidied up the Signal class and added a call counter to SignalBinding.
Added onRemovedFromWorld signal. Not currently used anywhere, but will be.
Tidied up the jsdocs.
Buttons are now waiting to be told when they're removed from the World.
You can now call Tween.to again on a Tween that has already completed. This will re-use the same tween, on the original object, without having to recreate the Tween again. This allows a single tween instance to be re-used multiple times, providing they are linked to the same object (thanks InsaneHero)
New build files.
Texture width is recalculated larger on subsequent call to updateText() when text has a stroke thickness > 1

In function override Phaser.Text.prototype.updateText(), don't include this.context.lineWidth in width calculation as it's already incorporated by this.style.strokeThickness.
Add support for "rgba" to Phaser.Stage.backgroundColor

 - backgroundColor now uses valueToColor which supports hex strings, web/rgba strings, and hex numbers.
 - valueToColor normalizes across hexToColor/webToColor/getRGB; see comments
 - hexToColor now documents the prefix being optional and allows the `0x` prefix.
 - webToColor now exctracts an alpha channel if present - as a slight misfeature it will also accept `rgb(..,a)`.
Fixed return value of Polygon.contains

Polygon.contains was toggling the return value on each valid hit.