grafx - Extensible Java Graphics Package Code

Rename alias(double) to pixel(double). For clarity. About to rename chop() as
well, probably to alias() this time.

Putting some finishing touches on the 2D rendering library.

Doing better casting to 32 bit floating point in fillPolygon().

Finally doing away with m_foff in 2D graphics.

Starting to phase out m_foff in 2D graphics. in setClip(), computing the
integer min/max values directly with alias(), and offsetting by 0.5d in one
direction or the other.

Improving the line drawing routines in 2D graphics by using the new alias()
function. This no longer uses m_foff. The casts are now done when the value
is in the interval [1.0,2.0].

This is the new way of using the cast to truncate accumulation errors.

Embellishing CastCorrectness.

Adding a missing '/' character in comment.

Adding class CastCorrectness.