Also extend the 'idlelib' section header. These additions affect both the displayed idle.html file and the contents.html file displayed by clicking the Complete table of contents link on the main docs.python.org page. (The module index entries are generated from the module name and synopsis within module files.)
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Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
Create a template for minimally testing a tkinter-using module by importing it and instantiating its class(es). Add a test file for all non-startup IDLE modules. Edit existing files and update coverage. This is part 1 of 3, covering the 21 autocomplete to help modules and touching 33 idlelib files.