Add docs on the new param globalPos

Fix thne name of the param

Give the possibility to get the local position with your own global position. ...

Save the global position in the changedTouches event object.
This feature give us the possibility to manage multitouch event in the save object ex: Resizing Gesture event with two touch moving in the save time.

swapped b and c in getLocalPosition()

jsdoc fixes for the whole of the WebGL renderer classes, Utils and a few updates to the Interaction classes. And that's it - I'm done!

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;
}

Removed this.local in InteractionData fixes #654

Tweaked getLocalPosition ...

Also cahced css cursor reference in js

Fixed, finally adapted to the dev branch