Enable nova-volume by default

Change-Id: I624eaab54619ef0ea6aec980df4a26e019b9674a
diff --git a/stack.sh b/stack.sh
index 61e7356..c744853 100755
--- a/stack.sh
+++ b/stack.sh
@@ -183,7 +183,7 @@
 M_MAC_RANGE=${M_MAC_RANGE:-404040/24}
 
 # Specify which services to launch.  These generally correspond to screen tabs
-ENABLED_SERVICES=${ENABLED_SERVICES:-g-api,g-reg,key,n-api,n-crt,n-obj,n-cpu,n-net,n-sch,n-novnc,n-xvnc,n-cauth,horizon,mysql,rabbit}
+ENABLED_SERVICES=${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}
 
 # Name of the lvm volume group to use/create for iscsi volumes
 VOLUME_GROUP=${VOLUME_GROUP:-nova-volumes}