Only the suggested changes that cause backward incompatibility were considered for now.
* Removed pyFXSThicknessShader that is identical with pyConstantThicknessShader.
* Swapped the order of two arguments of the pyDecreasingThicknessShader constructor
in line with other shaders taking the same arguments.
* Made module functions smoothC and get_fedge into methods of relevant shader classes.
* Removed pyExtremitiesOrientationShader that relied on undefined Stroke methods.