Improve interlinking of archiving/compression modules docs.

- Remove duplicate list of links to the other modules from each
  module’s doc (people can already go up to library/archiving and
  there they can see the list).

- Link to shutil high-level operations.

Reviewed by Nadeem Vawda in #6715.
diff --git a/Doc/library/shutil.rst b/Doc/library/shutil.rst
index 78c38e5..a330018 100644
--- a/Doc/library/shutil.rst
+++ b/Doc/library/shutil.rst
@@ -31,6 +31,8 @@
    are not copied.
 
 
+.. _file-operations:
+
 Directory and files operations
 ------------------------------
 
@@ -185,7 +187,7 @@
    .. versionadded:: 2.3
 
 
-.. _shutil-example:
+.. _copytree-example:
 
 copytree example
 ::::::::::::::::
@@ -254,8 +256,13 @@
    copytree(source, destination, ignore=_logpath)
 
 
-Archives operations
--------------------
+.. _archiving-operations:
+
+Archiving operations
+--------------------
+
+High-level utilities to create and read compressed and archived files are also
+provided.  They rely on the :mod:`zipfile` and :mod:`tarfile` modules.
 
 .. function:: make_archive(base_name, format, [root_dir, [base_dir, [verbose, [dry_run, [owner, [group, [logger]]]]]]])
 
@@ -322,6 +329,8 @@
    .. versionadded:: 2.7
 
 
+.. _archiving-example:
+
 Archiving example
 :::::::::::::::::
 
@@ -346,5 +355,3 @@
     -rw------- tarek/staff    1675 2008-06-09 13:26:54 ./id_rsa
     -rw-r--r-- tarek/staff     397 2008-06-09 13:26:54 ./id_rsa.pub
     -rw-r--r-- tarek/staff   37192 2010-02-06 18:23:10 ./known_hosts
-
-