Put Catalyst trunk ports on VLAN 1 by default

Change-Id: I5431c12f56d2d9220878a8a5c9e8674116327fde
diff --git a/drivers/CiscoCatalyst.py b/drivers/CiscoCatalyst.py
index 50fb18e..2db91b4 100644
--- a/drivers/CiscoCatalyst.py
+++ b/drivers/CiscoCatalyst.py
@@ -238,6 +238,7 @@
             self._cli("switchport mode %s" % mode)
             if mode == "trunk":
                 self._cli("switchport trunk encapsulation dot1q")
+                self._cli("switchport trunk trunk native vlan 1")
             self._end_configure()
 
             # Validate it happened