Issue #10446: Several changes to module documentation generated by pydoc:

1. Online reference manual link is now version-specific and the
   'MODULE DOCS' section renamed to 'MODULE REFERENCE'.

2. 'FILE' section is moved to the end of the file.

3. Special names processed by pydoc such as __version__ or __credits__
   are now excluded from the DATA section.

4. Defined __all__ to prevent pydoc from exposing undocumented details
   about itself.

5. Removed Python 2.3 compatibility code.
diff --git a/Doc/library/pydoc.rst b/Doc/library/pydoc.rst
index 4103dd4..cbb8af8 100644
--- a/Doc/library/pydoc.rst
+++ b/Doc/library/pydoc.rst
@@ -63,7 +63,9 @@
 Python interpreter and typed ``import spam``.
 
 Module docs for core modules are assumed to reside in
-http://docs.python.org/library/.  This can be overridden by setting the
-:envvar:`PYTHONDOCS` environment variable to a different URL or to a local
-directory containing the Library Reference Manual pages.
+``http://docs.python.org/X.Y/library/`` where ``X`` and ``Y`` are the
+major and minor version numbers of the Python interpreter.  This can
+be overridden by setting the :envvar:`PYTHONDOCS` environment variable
+to a different URL or to a local directory containing the Library
+Reference Manual pages.