Split TextViewer class into ViewWindow, ViewFrame, and TextFrame classes so that instances
of the latter two can be placed with other widgets within a multiframe window.
Patch by Cheryl Sabella.
(cherry picked from commit 42bc8be)
(cherry picked from commit 054e09147a)
* bpo-30290: IDLE: Refactor help_about to PEP8 names (#1714)
Patch by Cheryl Sabella.
(cherry picked from commit 5a346d5dbc)
* IDLE test_help_about: edit and add test. (#1838)
Coverage is now 100%
(cherry picked from commit eca7da0f13)
terryjreedy