Update devstack supported OS's on documentation
Since Feb 25th devstack supported operating systems changed
due to Nova increasing its minimum required libvirt version.
Further details see: I6617283afd798af37e64913b7865cea3c8a62aba
This patch is to update versions on devstack documentation.
Change-Id: I12bb59b0903a728376ee9422213c2903b9138249
diff --git a/doc/source/index.rst b/doc/source/index.rst
index edd6595..eb10bdd 100644
--- a/doc/source/index.rst
+++ b/doc/source/index.rst
@@ -39,7 +39,7 @@
-------------
Start with a clean and minimal install of a Linux system. Devstack
-attempts to support Ubuntu 14.04/16.04, Fedora 23/24, CentOS/RHEL 7,
+attempts to support Ubuntu 16.04/17.04, Fedora 24/25, CentOS/RHEL 7,
as well as Debian and OpenSUSE.
If you do not have a preference, Ubuntu 16.04 is the most tested, and