- minor UI changes for Gerber UI

- ~~after an object move, the apertures plotted shapes are deleted from canvas and the 'mark all' button is deselected~~
- after move tool action or any other transform (rotate, skew, scale, mirror, offset), the plotted apertures are kept plotted.
- changing units now will convert all the default values from one unit type to another
- prettified the selection shape and the moving shape
- initial work in object hovering shape

flatcamTools/ToolCalculators.py

@@ -244,7 +244,7 @@ class ToolCalculator(FlatCAMTool):
         FlatCAMTool.install(self, icon, separator, shortcut='ALT+C', **kwargs)
 
     def set_tool_ui(self):
-        self.units = self.app.ui.general_options_form.general_app_group.units_radio.get_value().upper()
+        self.units = self.app.ui.general_defaults_form.general_app_group.units_radio.get_value().upper()
 
         ## Initialize form
         self.mm_entry.set_value('0')