Add 'cache_query_string' configuration option

Close #2349
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index fb97f94..38fd759 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -505,8 +505,8 @@
       -  Added a second argument to method ``set_content_type()`` that allows setting the document charset as well.
       -  Added methods ``get_content_type()`` and ``get_header()``.
       -  Added method ``delete_cache()``.
+      -  Added configuration option ``$config['cache_query_string']`` to enable taking the query string into account when caching.
       -  Changed caching behavior to compress the output before storing it, if ``$config['compress_output']`` is enabled.
-      -  Changed caching to take the query string into account.
 
    -  :doc:`Config Library <libraries/config>` changes include: