Fixed a straggling reference to the old version of Tween.
Fixed a straggling reference to the old version of Tween.

This should have gone in with pull request #354.

CesiumGS/cesium,denverpierce/cesium,emackey/cesium,CesiumGS/cesium,omh1280/cesium,jasonbeverage/cesium,geoscan/cesium,kiselev-dv/cesium,wallw-bits/cesium,wallw-bits/cesium,jason-crow/cesium,oterral/cesium,ggetz/cesium,wallw-bits/cesium,kiselev-dv/cesium,AnimatedRNG/cesium,denverpierce/cesium,josh-bernstein/cesium,likangning93/cesium,aelatgt/cesium,AnimatedRNG/cesium,emackey/cesium,jason-crow/cesium,omh1280/cesium,hodbauer/cesium,oterral/cesium,emackey/cesium,emackey/cesium,esraerik/cesium,CesiumGS/cesium,ggetz/cesium,aelatgt/cesium,likangning93/cesium,YonatanKra/cesium,YonatanKra/cesium,esraerik/cesium,omh1280/cesium,NaderCHASER/cesium,omh1280/cesium,aelatgt/cesium,likangning93/cesium,likangning93/cesium,progsung/cesium,ggetz/cesium,oterral/cesium,ggetz/cesium,AnalyticalGraphicsInc/cesium,kaktus40/cesium,NaderCHASER/cesium,jason-crow/cesium,esraerik/cesium,hodbauer/cesium,denverpierce/cesium,denverpierce/cesium,aelatgt/cesium,AnimatedRNG/cesium,josh-bernstein/cesium,NaderCHASER/cesium,CesiumGS/cesium,geoscan/cesium,kiselev-dv/cesium,soceur/cesium,YonatanKra/cesium,hodbauer/cesium,jason-crow/cesium,jasonbeverage/cesium,progsung/cesium,kaktus40/cesium,AnimatedRNG/cesium,wallw-bits/cesium,YonatanKra/cesium,AnalyticalGraphicsInc/cesium,kiselev-dv/cesium,esraerik/cesium,soceur/cesium,soceur/cesium,likangning93/cesium,CesiumGS/cesium