Adjusted PolyPoint module. Added module spec dir.

The polypoint class was made a little bit more robust. There is now a points
method as well as a points_array method.  The points method returns all of the
individual point instances as an array where as the point_array returns an
assoc array of actual integer value points.

The is_closed? method in PolyPoint now simply checks to see if the type is a Line.
Lines are open the other core PolyPoint shapes are all closed.

Finally a spec/module folder was added.