This follows the previous patch that changed idlelib file names.
Class names that matched old module names are not changed.
Change idlelib imports in turtledemo.__main__.
Exception: config-extensions.def. Previously, extension section
names, file names, and class names had to match. Changing section
names would create cross-version conflicts in config-extensions.cfg
(user customizations). Instead map old names to new file names
at point of import in editor.EditorWindow.load_extension.
Patch extensively tested with test_idle, idle_test.htest.py, a custom
import-all test, running IDLE in a console to catch messages,
and testing each menu item. Based on a patch by Al Sweigart.
The new idlelib/idle.html is copied from Doc/build/html/idle.html.
It looks better than help.txt and will better document Idle as released.
The tkinter html viewer that works for this file was written by Rose Roseman.
The new code is in idlelib/help.py, a new file for help menu classes.
The now unused EditorWindow.HelpDialog class and helt.txt file are deprecated.
consolidating and improving human-validated tests of Idle. Change other files
as needed to work with htest. Running the module as __main__ runs all tests.
