I define a frame for positioning some morph in a proportional layout.

Instance variables:
leftFraction
topFraction
rightFraction
bottomFraction <Float> The fractional distance (between 0 and 1) to place the morph in its owner's bounds
leftOffset
topOffset
rightOffset
bottomOffset <Integer> Fixed pixel offset to apply after fractional positioning (e.g., "10 pixel right of the center of the owner")

	layout
	layout:in:

	objects from disk
	convertToCurrentVersion:refStream: negateBottomRightOffsets

	accessing	top
	bottomFraction
	bottomFraction:
	bottomFraction:offset:
	bottomOffset
	bottomOffset:
	leftFraction
	leftFraction:
	leftFraction:offset:
	leftOffset
	leftOffset:
	rightFraction
	rightFraction:
	rightFraction:offset:
	rightOffset
	rightOffset:
	topFraction
	topFraction:
	topFraction:offset:
	topOffset
	topOffset:

	layout	top
	layout:in: Return the proportional rectangle insetting the given bounds

	objects from disk	top
	convertToCurrentVersion:refStream: JW 2/1/2001
	negateBottomRightOffsets

	as yet unclassified	top
	classVersion Default. Any class may return a later version to inform readers that use ReferenceStream. 8/17/96 tk
	fractions:offsets: