[Drawkit] Fix for DKArcPath and margin changes

[Brad Larson]

Currently, DKArcPath elements don't respond to changes in the margin  
size, if that change results in a shift of the drawing origin.  To fix  
this, you can add the following to DKArcPath.m:

- (void)			applyTransform:(NSAffineTransform*) transform
{
	[self notifyVisualChange];
	[[self path] transformUsingAffineTransform:transform];
	mCentre = [transform transformPoint:mCentre];
	[self notifyVisualChange];
}

This makes sure that the center point of the arc is translated properly.

______________________
Brad Larson
SonoPlot, Inc.
3030 Laura Lane, Suite 120
Middleton, WI 53562