createVariable will not reuse the same backend such as copy
cosmetics
change RowAccumulator generic parameter to less strict
add EuclideanSpace to real-coordinate transformations
added singleton inverseperspective3d and use it
added AbstractARGDoubleType, ARGBDoubleType and NativeARGBDoubleType
added Composite type and CompositeView
added Composite to ARGBDouble converter
added ARGBDouble to ARGBType converter
added argbdoublelayers as a RowAccumulator
modified volume renderer for testing, uses composites and argbdoubles
added interactive examples for demonstration of composites and argbdoubles,
referenced binary images missing