A morph that serves as a thumbnail of a given form.

	thumnail creation
	makeThumbnailFromForm:

	initialization	top
	initialize Initialize the receiver
	maxWidth:minHeight: Set the min and max heights and widths as indicated
	setStandardDefaultMetrics Provide the current choices for min.max width/height for thumbnails

	thumnail creation	top
	makeThumbnailFromForm: Make a thumbnail from the form provided, obeying my min and max width and height preferences