Updated vector tests to account for non-zero floating point arithmetic.
Removed Array class. Derived classes can't maintain references to parent array elements and support assignment (references can only be sent once). Another possibility would be to have the parent class maintain pointers to derived class properties but I was sick of all the hacking to only save on a few shared features between Vector, Point, Pixel, and Dimension. I broke each into their own templated classes for easier maintability and extendability.