upstream commit

correct description of UpdateHostKeys in ssh_config.5 and
 add it to -o lists for ssh, scp and sftp; pointed out by jmc@
diff --git a/sftp.1 b/sftp.1
index 7eb9970..9eed155 100644
--- a/sftp.1
+++ b/sftp.1
@@ -1,4 +1,4 @@
-.\" $OpenBSD: sftp.1,v 1.99 2014/04/22 14:16:30 jmc Exp $
+.\" $OpenBSD: sftp.1,v 1.100 2015/01/26 12:16:36 djm Exp $
 .\"
 .\" Copyright (c) 2001 Damien Miller.  All rights reserved.
 .\"
@@ -22,7 +22,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: April 22 2014 $
+.Dd $Mdocdate: January 26 2015 $
 .Dt SFTP 1
 .Os
 .Sh NAME
@@ -243,6 +243,7 @@
 .It ServerAliveCountMax
 .It StrictHostKeyChecking
 .It TCPKeepAlive
+.It UpdateHostKeys
 .It UsePrivilegedPort
 .It User
 .It UserKnownHostsFile