[4.0] 785458f Add info about X-F-F

[Lasse Karstensen]

commit 785458ff2e6f57f13ff7a3938fe4994b6115dcb1
Author: Andreas Plesner <apj at mutt.dk>
Date:   Tue Nov 18 08:50:43 2014 +0100

    Add info about X-F-F

diff --git a/doc/sphinx/whats-new/upgrading.rst b/doc/sphinx/whats-new/upgrading.rst
index 2ee8ae7..0e5b800 100644
--- a/doc/sphinx/whats-new/upgrading.rst
+++ b/doc/sphinx/whats-new/upgrading.rst
@@ -185,6 +185,14 @@ The `remove` keyword is gone
 Replaced by `unset`.
 
 
+X-Forwarded-For is now set before vcl_recv
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In many cases, people unintentionally removed X-Forwarded-For when
+implementing their own vcl_recv. Therefore it has been moved to before
+vcl_recv, so if you don't want an IP added to it, you should remove it
+in vcl_recv.
+
 
 Changes to existing parameters
 ==============================