Currently, the tabs on the configdialog's Notebook only have a text description. I propose we add icons to the tabs to make them a little more colourful, new-user-friendly, etc.

I have drafted a version which uses icons found in the Public Domain (I can provide links if this would be helpful - I believe the changes I have made would be covered under the CLA) resized to a height of 25px (see attached). The shown icons are meant more as a demonstration of this feature than a "I want these particular icons in the patch" but feel these make the dialog seem more inviting.

I have nosied Mark Roseman as this idea came from the sort of changes described on the IDLE modernisation case study (https://tkdocs.com/tutorial/idle.html)