grafx - Extensible Java Graphics Package Code

made lots of changes to RasterFloatGraphics:
- added hook to do alpha manipulation (RasterFloatPixBuff).
- condensed a lot of code, and put it into new classes FloatPolyEdge and
FloatPolyClipper.
- cleaned up implementation of clear().
- fixed up color conversions between FloatColor and int.

my next goal is to fix any bugs that these changes may have created, and to
implement a FloatPolyEdge pool, so that 'new' would not have to be called for
every FloatPolyEdge; drawing many polygons would otherwise lead to rapid
memory allocation and de-allocation and re-allocation (new edges created all
the time).

updating javadoc.

adding a little spiffy clip technology to the simple demo.

adding constructor to FloatColor for opaque colors.

removing a still immature class. will re-add later, at a more mature stage.

adding DepthGraphics interface (first draft).
cleaning up the color interface by adding FloatColor. FloatColor will be
used by DepthGraphics to interpolate colors.
removing unuseful classes in com.nerius.grafx which made dependency on
com.nerius.grafx.img. now, com.nerius.grafx has no dependency on any
package that is not part of standard java-1.0. Rasterizor and
AnimatingRasterizor have been removed.

creating com.nerius.grafx java package on sourceforge.net.

initial checkin

Standard project directories initialized by cvs2svn.