function Ease() {
		throw "Ease cannot be instantiated.";
	}
The Ease class provides a collection of easing functions for use with TweenJS. It does not use the standard 4 param
easing signature. Instead it uses a single param which indicates the current linear ratio (0 to 1) of the tween.

Most methods on Ease can be passed directly as easing functions:

     Tween.get(target).to({x:100}, 500, Ease.linear);

However, methods beginning with "get" will return an easing function based on parameter values:

     Tween.get(target).to({y:200}, 500, Ease.getPowIn(2.2));

Please see the <a href="http://www.createjs.com/Demos/TweenJS/Tween_SparkTable">spark table demo</a> for an
overview of the different ease types on <a href="http://tweenjs.com">TweenJS.com</a>.

<em>Equations derived from work by Robert Penner.</em>
@class Ease
@static