minor #3820 Update page_creation.rst (adreeun)

This PR was submitted for the 2.4 branch but it was merged into the 2.3 branch instead (closes #3820).

Discussion
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Update page_creation.rst

Apache's directory index documentation link outdated - replaced <2.0> in the link with <2.4>

Commits
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32508f2 Update page_creation.rst
e0cb998 Update page_creation.rst

Author: weaverryan

Diff for: book/page_creation.rst

@@ -1061,5 +1061,5 @@ to rapidly develop applications.
 .. _`Twig`: http://twig.sensiolabs.org
 .. _`third-party bundles`: http://knpbundles.com
 .. _`Symfony Standard Edition`: http://symfony.com/download
-.. _`Apache's DirectoryIndex documentation`: http://httpd.apache.org/docs/2.0/mod/mod_dir.html
+.. _`Apache's DirectoryIndex documentation`: http://httpd.apache.org/docs/current/mod/mod_dir.html
 .. _`Nginx HttpCoreModule location documentation`: http://wiki.nginx.org/HttpCoreModule#location