- refactored some methods from App class and moved them to plotcanvas (plotcanvaslegacy) class

- added an label with icon in the status bar, clicking it will toggle (show status) of the X-Y axis on cavnas
- optimized the UI, added to status bar an icon to toggle the axis

AppEditors/FlatCAMTextEditor.py

@@ -214,10 +214,10 @@ class TextEditor(QtWidgets.QWidget):
             filename = str(FCFileSaveDialog.get_saved_filename(
                 caption=_("Export Code ..."),
                 directory=self.app.defaults["global_last_folder"] + '/' + str(obj_name),
-                filter=_filter_
+                ext_filter=_filter_
             )[0])
         except TypeError:
-            filename = str(FCFileSaveDialog.get_saved_filename(caption=_("Export Code ..."), filter=_filter_)[0])
+            filename = str(FCFileSaveDialog.get_saved_filename(caption=_("Export Code ..."), ext_filter=_filter_)[0])
 
         if filename == "":
             self.app.inform.emit('[WARNING_NOTCL] %s' % _("Cancelled."))