Issue #16893: Replace help.txt with idle.html for Idle doc display.
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.
diff --git a/Lib/idlelib/help.txt b/Lib/idlelib/help.txt
index eed89c0..296c78b 100644
--- a/Lib/idlelib/help.txt
+++ b/Lib/idlelib/help.txt
@@ -1,3 +1,7 @@
+This file, idlelib/help.txt is out-of-date and no longer used by Idle.
+It is deprecated and will be removed in the future, possibly in 3.6
+----------------------------------------------------------------------
+
[See the end of this file for ** TIPS ** on using IDLE !!]
File Menu: