At one time, ConfigDialog was given a do-nothing Help button. It was diabled a couple of years ago. This patch restores it for both config dialogs, displaying a text appropriate for both. There are separate functions in anticipation of dialog-specific content. For both, there is the issue of when changes take effect (#22707). For extensions, there might be extension-specific help (#22705).
This patch does two things: 1. restore the Help button and make it display something; 2. lower case the method names. The latter is a separate issue, best done in a new file. What is needed for #25313 is tab-specific text. Also, now that Config Extenstion uses a list rather than tabs, it couldn be added as a tab to the main dialog, and only one set of button event handlers would be needed. Tab-specific text would be needed first.
I'm not against online help, but I feel that what's there wouldn't be helpful to someone using IDLE. Once this would be extended to per-tab, what are the problem areas that people really need help with? Also keeping in mind we're going to be replacing this dialog (at least for people with tk > 8.4) in the not too distant future.
I rewrote the common section to explain what the button do. I did not modify the extensions dialog because I want to finish #24782. #22707 may add more.
