- converted from Python2 code to Python3 code

- in camlib.py, CNCJob class -> generate_from_excellon_by_tool() was
failing in the line to sort the tools due of been unable to compare
between dict's. I replaced that section.

tclCommands/TclCommandAddRectangle.py

@@ -1,8 +1,8 @@
 from ObjectCollection import *
-import TclCommand
+from tclCommands.TclCommand import TclCommandSignaled
 
 
-class TclCommandAddRectangle(TclCommand.TclCommandSignaled):
+class TclCommandAddRectangle(TclCommandSignaled):
     """
     Tcl shell command to add a rectange to the given Geometry object.
     """