bpo-33820: Update idlelib subsection of What's New 3.6

Doc/whatsnew/3.6.rst

@@ -1142,6 +1142,42 @@ In compensation, the eventual result with be that some idlelib classes will be
 easier to use, with better APIs and docstrings explaining them.  Additional
 useful information will be added to idlelib when available.
 
+New in 3.6.2:
+
+Multiple fixes for autocompletion. (Contributed by Louie Lu in :issue:`15786`.)
+
+New in 3.6.3:
+
+Module Browser (on the File menu, formerly called Class Browser),
+now displays nested functions and classes in addition to top-level
+functions and classes.
+(Contributed by Guilherme Polo, Cheryl Sabella, and Terry Jan Reedy
+in :issue:`1612262`.)
+
+The IDLE features formerly implemented as extensions have been reimplemented
+as normal features.  Their settings have been moved from the Extensions tab
+to other dialog tabs.
+(Contributed by Charles Wohlganger and Terry Jan Reedy in :issue:`27099`.)
+
+The Settings dialog (Options, Configure IDLE) has been partly rewritten
+to improve both appearance and function.
+(Contributed by Cheryl Sabella and Terry Jan Reedy in multiple issues.)
+
+New in 3.6.4:
+
+The font sample now includes a selection of non-Latin characters so that
+users can better see the effect of selecting a particular font.
+(Contributed by Terry Jan Reedy in :issue:`13802`.)
+The sample can be edited to include other characters.
+(Contributed by Serhiy Storchaka in :issue:`31860`.)
+
+New in 3.6.6:
+
+Editor code context option revised.  Box displays all context lines up to
+maxlines.  Clicking on a context line jumps the editor to that line.  Context
+colors for custom themes is added to Highlights tab of Settings dialog.
+(Contributed by Cheryl Sabella and Terry Jan Reedy in :issue:`33642`,
+:issue:`33768`, and :issue:`33679`,
 
 importlib
 ---------