Update src/utils/math/class.vector2D.js

Add a bunch of vector math functions.  Some math functions return a new vector and there are new functions that will modify the vector.
Update src/utils/class.region.js

changed substract to subtract
Update src/node/class.node.js

changed code to use new vector/position math functions
Update src/utils/math/class.vector2D.js

Forgot to remove an = sign
Update src/utils/math/class.vector2D.js

And a ,  Hopefully the last update to some simple functions!
rename version to v2.0.0-SNAPSHOT.
update minimified file and JSDoc
rename version to v2.0.0-SNAPSHOT.
update minimified file and JSDoc
- Evolution. CGSGNode : new events : onBeforeRender and onAfterRender
- Evolution. CGSGNode : new invalidate method
- Evolution. CGSGNode : new caching system with new "setPreComputed" method
- Evolution. Custom CGSGNode : ease of overriding render and renderGhost method
- Evolution. new Clipping item
- Evolution. new EventManager system
- Evolution. CGSGNode : new "getLocalZIndex", "setLocalZIndexToLast", "setLocalZIndex", "moveLocalZIndex"
- Evolution : rename "CGSGScene" to "CGSGView"
Add shadows properties
Add shadows properties
Apply rotation on the bounding box.
Add new Event Manager and Mask
Add new Event Manager and Mask
few renames and optimizations
Externalization of the animation manager
New animation manager
New animation manager
Externalization of the sceneGraph instance into the CGSG object.
remove useless parameter to CGSGNodeSprite