grafx - Extensible Java Graphics Package Code

Modifying the Sourceforge-hosted grafx webpage.

Saving the Sourceforge web files in SVN.

Delaying the increment/decrement of dydx in the last two remaining line-draw
routines that were awaiting optimization.

Finished optimizing drawLineNegDxDy(), but the performance gains here are much
less significant.

Starting to optimize drawLineNegDxDy(); showing how to do it algebraically, by
doing a "+ (1 - 1)" to a value.

Adding Int32AddPerformance and Int32DividePerformance. Integer divisions are
bad because of the exception handling (ArithmeticException I think).

Optimizing drawLinePosDxDy() just a hair, by pre-computing a slightly different
'xf' and then delaying the decrement to the end of the loop. It's slightly
faster in all cases now. This relies on the fact that [(yy + 1) * dxdy] is
equal to [yy * dxdy + dxdy]. Chopping that "+ dxdy" off essentially.

Adding grafx-2.3-RELNOTES.txt in case I ever lose the README.txt from
Sourceforge file download pages.

Making a release grafx-2.3.

Removing hashCode() from ClipRectangle because I don't like all of these
Java-isms. In fact I'm almost ready to jump ship and try Rust or D.