Update aggregates test for aggregates bp

Instead of implementing availability zones in the service table,
availability zones will be implemented using general aggregate metadata.

So when an aggregate is created it will already have metadata.

Part of blueprint aggregate-based-availability-zones

Change-Id: I0fd22399b99a14087fef63fc91d0baef746efbed
diff --git a/exercises/aggregates.sh b/exercises/aggregates.sh
index adc3393..deb1a03 100755
--- a/exercises/aggregates.sh
+++ b/exercises/aggregates.sh
@@ -99,8 +99,8 @@
 META_DATA_2_KEY=foo
 META_DATA_3_KEY=bar
 
-#ensure no metadata is set
-nova aggregate-details $AGGREGATE_ID | grep {}
+#ensure no additional metadata is set
+nova aggregate-details $AGGREGATE_ID | egrep "{u'availability_zone': u'$AGGREGATE_A_ZONE'}|{}"
 
 nova aggregate-set-metadata $AGGREGATE_ID ${META_DATA_1_KEY}=123
 nova aggregate-details $AGGREGATE_ID | grep $META_DATA_1_KEY
@@ -117,7 +117,7 @@
 nova aggregate-details $AGGREGATE_ID | grep $META_DATA_2_KEY && die "ERROR metadata was not cleared"
 
 nova aggregate-set-metadata $AGGREGATE_ID $META_DATA_3_KEY $META_DATA_1_KEY
-nova aggregate-details $AGGREGATE_ID | grep {}
+nova aggregate-details $AGGREGATE_ID | egrep "{u'availability_zone': u'$AGGREGATE_A_ZONE'}|{}"
 
 
 # Test aggregate-add/remove-host