Optimize Color to AWT conversions.

Color has a set() method that internally caches the AWT color it will
set on the Graphics2D context. This cached value is never returned,
because it is mutable.
Optimize Point memory usage.

Points no longer extends from AbstractRecord but implements Map and
IOrderedFields itself. This avoids unnecessary map object creation.
Optimize getGeneralPath.

This small optimization avoids calling getPointCount(), avoiding the
creation of some iterator objects.
Optimize core NodeContext methods.

invokeNode is an inner method in the render loop and took up a lot of
time. Instead of using a List, we now initialize it with an Object
array, making the method much faster.