vtysh:address-family vpnv6 and vpnv6 unicast added to resolve

" % Ambiguous command."
Fixes bug #950

Signed-off-by: Balaji Gurudoss <balajig81@gmail.com>

vtysh/extract.pl.in

@@ -49,6 +49,8 @@ $ignore{'"address-family ipv6"'} = "ignore";
 $ignore{'"address-family ipv6 (unicast|multicast)"'} = "ignore";
 $ignore{'"address-family vpnv4"'} = "ignore";
 $ignore{'"address-family vpnv4 unicast"'} = "ignore";
+$ignore{'"address-family vpnv6"'} = "ignore";
+$ignore{'"address-family vpnv6 unicast"'} = "ignore";
 $ignore{'"address-family ipv4 vrf NAME"'} = "ignore";
 $ignore{'"address-family encap"'} = "ignore";
 $ignore{'"address-family encapv4"'} = "ignore";