docs: add news item and link release notes for 10.6.8

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
diff --git a/docs/index.html b/docs/index.html
index b319732..b814a06 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -16,6 +16,12 @@
 
 <h1>News</h1>
 
+<h2>September 20, 2015</h2>
+<p>
+<a href="relnotes/10.6.8.html">Mesa 10.6.8</a> is released.
+This is a bug-fix release.
+</p>
+
 <h2>September 12, 2015</h2>
 <p>
 <a href="relnotes/11.0.0.html">Mesa 11.0.0</a> is released.  This is a new