Merge #317 ...

Adding support for pooling Point objects in
PIXI.InteractionData.prototype.getLocalPosition

In certain use cases, such as dragging, events are fired off in rapid
succession.

Creating a new PIXI.Point in each event can cause memory usage to build up
and trigger a nasty garbage collection event.

This commit allows you to pass in a point instead of allocating a new one
each time the method is called.

Sample usage would be something like this:

var newPosition = new PIXI.Point();

myContainer.mousemove = function(data) {
	data.originalEvent.preventDefault();

	this.data.getLocalPosition(this.parent, newPosition);

	this.position.x = newPosition.x;
	this.position.y = newPosition.y;
}

Merge pull request #909 from FedeOmoto/dev ...

Fix WebGLStencilManager.destroy method to destroy the stencilStack

Merge branch 'panrafal-feature/transparent-unmultiplied' into dev

merge #737

Add docs to new displayobject methods

manually merge #803

whitespace cleanup

Fix WebGLStencilManager.destroy method to destroy the stencilStack

Merge pull request #811 from MortimerGoro/dev ...

Improved CocoonJS touch support: compatibility with user defined styles

Merge pull request #853 from Fishrock123/dev ...

Fix arguments leakage in fn.bind polyfill

Merge pull request #859 from n1313/patch-1 ...

Improved handling of children removal from empty DisplayObjectContainers

Merge pull request #896 from JaapRood/fix/window-ref ...

Fixed references to global variables (window, document) that prevent Pixi from being loaded into environments that don’t necessarily have these available (like Node)

Merge pull request #906 from FedeOmoto/dev ...

Unused properties in WebGLMaskManager constructor

Merge branch 'dev' of https://github.com/GoodBoyDigital/pixi.js into dev

Add Render Texture invalid size check

TilingSprite._renderWebGL: missing mask argument in renderSession.maskManager.popMask call

Fix complexPrimitiveShader reference in WebGLStencilManager.bindGraphics method

Missing destroy of complexPrimitiveShader in WebGLShaderManager.destroy method

Unused property in WebGLShaderManager constructor

Unused properties in WebGLMaskManager constructor (two more)

Unused properties in WebGLMaskManager constructor

Merge pull request #904 from FedeOmoto/dev ...

Unused property in WebGLGraphics.renderGraphics method

Unused property in WebGLGraphics.renderGraphics method

Merge pull request #900 from FedeOmoto/dev ...

Double assingment in Graphics.drawPath mathod

Double assingment in Graphics.drawPath mathod

Merge pull request #898 from photonstorm/dev ...

Guards against the texture crop width/height being zero (which crashes IE11)

Guards against the texture crop width/height being zero (which crashes IE11)

Fixed references to global variables (window, document) that prevent Pixi from being loaded into environments that don’t necessarily have these available (like Node)

Merge pull request #851 from FedeOmoto/dev ...

When handling a restored webgl context event, save the newly created context and remove the lost one

Merge pull request #887 from serprex/dev ...

Prefer bind over 'var scope = this;'