[issue23964] Update README documentation for IDLE tests.

[Al Sweigart]

New submission from Al Sweigart:

It took me a while to read through the idle_test documentation to figure out how to run the test. Similar to the Profiler documentation, I've added "Instant User's Manual" section at the top of the file, as well as edited the text and formatting a bit.

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components: IDLE
files: idle_test_readme.patch
keywords: patch
messages: 241099
nosy: Al.Sweigart
priority: normal
severity: normal
status: open
title: Update README documentation for IDLE tests.
versions: Python 3.5
Added file: http://bugs.python.org/file39035/idle_test_readme.patch

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue23964>
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