Documentation: Tween.addLabel() should be Tween.label()

[FumioNonaka]

TweenJS/src/tweenjs/Tween.js

Line 520 in 6a571a9

* @method addLabel

Tween.label() method calls AbstractTween.addLabel().
http://createjs.com/docs/tweenjs/classes/Tween.html#method_addLabel

[lannymcnie]

Thanks! Fixed and pushed. Online docs and zips are not updated, but will be during the next build.