#14056: Small improvements to the tarfile documentation.

Patch by Éric Araujo with help from Lars Gustäbel.
diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst
index d3956fd..b07850f 100644
--- a/Doc/library/tarfile.rst
+++ b/Doc/library/tarfile.rst
@@ -19,7 +19,8 @@
 
 Some facts and figures:
 
-* reads and writes :mod:`gzip`, :mod:`bz2` and :mod:`lzma` compressed archives.
+* reads and writes :mod:`gzip`, :mod:`bz2` and :mod:`lzma` compressed archives
+  if the respective modules are available.
 
 * read/write support for the POSIX.1-1988 (ustar) format.
 
@@ -176,6 +177,13 @@
    Is raised by :meth:`TarInfo.frombuf` if the buffer it gets is invalid.
 
 
+The following constants are available at the module level:
+
+.. data:: ENCODING
+
+   The default character encoding: ``'utf-8'`` on Windows, the value returned by
+   :func:`sys.getfilesystemencoding` otherwise.
+
 
 Each of the following constants defines a tar archive format that the
 :mod:`tarfile` module is able to create. See section :ref:`tar-formats` for
@@ -202,20 +210,15 @@
    The default format for creating archives. This is currently :const:`GNU_FORMAT`.
 
 
-The following variables are available on module level:
-
-
-.. data:: ENCODING
-
-   The default character encoding: ``'utf-8'`` on Windows,
-   :func:`sys.getfilesystemencoding` otherwise.
-
-
 .. seealso::
 
    Module :mod:`zipfile`
       Documentation of the :mod:`zipfile` standard module.
 
+   :ref:`archiving-operations`
+      Documentation of the higher-level archiving facilities provided by the
+      standard :mod:`shutil` module.
+
    `GNU tar manual, Basic Tar Format <http://www.gnu.org/software/tar/manual/html_node/Standard.html>`_
       Documentation for tar archive files, including GNU tar extensions.