grafx - Extensible Java Graphics Package Code

Adding class CastCorrectness.

Moving location of swap() to be more appropriate.

Some formatting changes in 2D line clipper, plus marking some parameters as
'final'.

Moving line clipping code to bottom of file. No other changes.

Updating Donut.

This may be another way of doing it.

Showing the approach of casting to float when the double is in range [0,2].

Reducing FF for COARSE_MESH, was 5, is now 3. It looks smooth.

Implemented FINE_WIREFRAME.

Adding LineRotate2D test code.