Changes to the linear transform from plot coords to view coords. Added more tests for zero, and rather than throwing an exception when the plot range is zero, the view coordinate of zero is returned instead.
Changes to the linear transform from plot coords to view coords.
Added more tests for zero, and rather than throwing an exception
when the plot range is zero, the view coordinate of zero is returned
instead.

Also made some changes in the scaleToFitPlots: method, so that
if the fitted plot range is zero, the plot space range is not updated.

escoz/core-plot,escoz/core-plot,escoz/core-plot,escoz/core-plot,escoz/core-plot