Fix #17119: Update cache doc to match current implementation, which does (since…

Fix #17119: Update cache doc to match current implementation, which does (since r15705) cache pages with GET parameters. Thanks Vanni, poirier, and calvinspealman.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17090 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/topics/cache.txt

@@ -456,8 +456,10 @@ Then, add the following required settings to your Django settings file:
   the site, or some other string that is unique to this Django instance, to
   prevent key collisions. Use an empty string if you don't care.
 
-The cache middleware caches every page that doesn't have GET or POST
-parameters. Optionally, if the :setting:`CACHE_MIDDLEWARE_ANONYMOUS_ONLY`
+The cache middleware caches GET and HEAD responses with status 200, where the request
+and response headers allow. Responses to requests for the same URL with different
+query parameters are considered to be unique pages and are cached separately.
+Optionally, if the :setting:`CACHE_MIDDLEWARE_ANONYMOUS_ONLY`
 setting is ``True``, only anonymous requests (i.e., not those made by a
 logged-in user) will be cached. This is a simple and effective way of disabling
 caching for any user-specific pages (including Django's admin interface). Note