[gtk+] Add a release not about GtkTable expand flags

[Matthias Clasen <matthiasc src gnome org>]

commit 0989614d2d94dec8bcc764d1e3c8180deead04a2
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Aug 1 09:09:19 2016 -0400

    Add a release not about GtkTable expand flags

 docs/reference/gtk/migrating-3xtoy.xml |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gtk/migrating-3xtoy.xml b/docs/reference/gtk/migrating-3xtoy.xml
index f140a4a..1040c12 100644
--- a/docs/reference/gtk/migrating-3xtoy.xml
+++ b/docs/reference/gtk/migrating-3xtoy.xml
@@ -433,5 +433,11 @@
       layout of those children to change, if they unintentionally had hexpand
       set before.
     </para>
+
+    <para>
+      The behavior of the expand flag in #GtkTables #GtkAttachOptions has been
+       changed to (again) match the behavior in #GtkBox and in GTK+ 2.x. These
+       options don't cause the table itself to expand.
+    </para>
   </section>
 </chapter>