PMTweenUnit and PMTweenPhysicsUnit can now have their startingValue properties set while tweening.
first additive commit
Implemented additive tweening in PMTweenUnit. Updated examples project to include additive demos. Updated README.
• Implemented additive animation in PMTweenUnit!
• Updated PMTweenObjectUpdater to provide additive updating support.
• Updated tests.
• Updated Examples project to include additive demos.