Fix secgroups exercise on postgres

This should fix the failing (but non-voting) postgres gate tests.

Why does postgresql change the value '0.0.0.0/00' to '0.0.0.0/0'?
Clearly the correct value for the network CIDR bits is with only
one zero but even an incorrect value shouldn't be changing.

SQLalchemy is given this for the column:
        Column('cidr', String(length=255)),

Change-Id: Ib19dad23789654664e90518087e5a462fa8b8034
diff --git a/exercises/sec_groups.sh b/exercises/sec_groups.sh
index f6810e3..fbd9c8e 100755
--- a/exercises/sec_groups.sh
+++ b/exercises/sec_groups.sh
@@ -48,7 +48,7 @@
 RULES_TO_ADD=( 22 3389 5900 )
 
 for RULE in "${RULES_TO_ADD[@]}"; do
-    nova secgroup-add-rule $SEC_GROUP_NAME tcp $RULE $RULE 0.0.0.0/00
+    nova secgroup-add-rule $SEC_GROUP_NAME tcp $RULE $RULE 0.0.0.0/0
 done
 
 # Check to make sure rules were added
@@ -63,7 +63,7 @@
 
 # Delete rules and secgroup
 for RULE in "${RULES_TO_ADD[@]}"; do
-    nova secgroup-delete-rule $SEC_GROUP_NAME tcp $RULE $RULE 0.0.0.0/00
+    nova secgroup-delete-rule $SEC_GROUP_NAME tcp $RULE $RULE 0.0.0.0/0
 done
 nova secgroup-delete $SEC_GROUP_NAME