Change the default mac range to not 0

This fixes some of the confusion caused by
Bug 947382

zoinks! set the U/L bit

Change-Id: I3a610e3aa3904fdb82ad314c3fd1d06c6017f46c
diff --git a/stack.sh b/stack.sh
index eead8a1..10da914 100755
--- a/stack.sh
+++ b/stack.sh
@@ -179,7 +179,7 @@
 # Default Melange Host
 M_HOST=${M_HOST:-localhost}
 # Melange MAC Address Range
-M_MAC_RANGE=${M_MAC_RANGE:-404040/24}
+M_MAC_RANGE=${M_MAC_RANGE:-FE-EE-DD-00-00-00/24}
 
 # Specify which services to launch.  These generally correspond to screen tabs
 ENABLED_SERVICES=${ENABLED_SERVICES:-g-api,g-reg,key,n-api,n-crt,n-obj,n-cpu,n-net,n-vol,n-sch,n-novnc,n-xvnc,n-cauth,horizon,mysql,rabbit}